50% of the world’s population live in urban areas. By 2050, this figure is expected to increase to 80%. Life in a megacity is both enchanting and problematic. The megacities are reality and Giga-cities are soon to be. On the same time, we are increasingly facing severe housing deprivation and environmental issues (peak oil, congested cities, plastic pollution). On top, alarming human signs (isolation, loneliness, inequalities and severe health issues) are on the rise due to our way of life. But why?
Danish architect Jan Gehl has studied human behavior in cities for decades. He teamed up with director Andreas Dalsgaard for a documentary to investigate the qualities and challenges in today’s urban environment. Their movie ‘The Human Scale‘ meets thinkers, architects and urban planners across the globe to question our assumptions about modernity and to explore what happens when we put people into the centre of our planning. “He has documented how modern cities repel human interaction, and argues that we can build cities in a way, which takes human needs for inclusion and intimacy into account” (IMDB).
Comparing the past, present and future of the world’s cities, it becomes obvious that Megacities today have many similarities with science-fiction visions from the 20th century. Skylines are dominated by gigantic skyscrapers.
Observing motorways, bus lanes and street networks, the American sociologist and philosopher of technology B. Ladd has stated that, “we are rapidly planning our life to fit the motor car” . Following this observation, ‘The Human Scale’ raises the question why architects and city planners are no longer interested in human scale. In other words, as cities provide increasingly faster opportunities for (e.g. in earning money) the importance of urban development should be based with the consideration of human needs of personality, warmth, intimacy and social interaction. The movie explores current city planning characteristics based on data insights and the drivers and effects of this development for human population. Ultimately the documentary explores how fundamental needs such as interaction, inclusion and intimacy could be translated into a redefinition or re-alignment of architecture in the 21st century.
According to Peter Smith, cities have changed much over the centuries, but their essential character has remained the same. Although always a dream, the ideal city has never existed, as he states:
“The quest for the ideal city has intrigued philosophers, architects and artists since antiquity. It has become the Holy Grail of architecture and town planning. Ideal cities are the ultimate aspirational location. Their plans are an expression of the geometry of living, forming the perfect physical environment, a union of aesthetics and functionality that serves a social, even an ethical, purpose. For the very structures and spaces of the ideal city instil a sense of order and fulfilment in their inhabitants.”Peter Smith, City: A Guidebook for the Urban Age, 2012
Practitioners and researchers in architecture are discussing ideas to explore new mathematics and “tools” to find solutions for managing urban change throughout the world. What if mass housing and increasingly higher buildings give rise to a loss of social interaction and relationships? Are next generations losing humanity because of unhuman architecture? How can privacy and public domains be redefined through new approaches in city-planning (e.g. the idea of vertical cities)? What should be seen as the role model for sustainable urban development?
From rural depopulation to mega cities
Since the Industrial Revolution of the late 18th century, traditional rural life appears to be under threat. Particulary, young people in rural settings increasingly seek opportunities that urban centres provide to them, says Paul Bairoch. Urbanisation has rapidly spread across the Western world and, since the 1950s, has begun to take hold in the developing world as well. With regard to the population in 1950, New York marked the largest agglomeration in the world containing 12.3 million inhabitants. „Presently, a city with New York’s 1950 population size would be only the world’s sixth largest city. In 2013, 24 cities have a population in exces of 20 million inhabitants, topped by Tokyo (at 37.2 million).“
Urbanisation is not merely a modern phenomenon, but a rapid and historic transformation of human social roots on a global scale. This development further results in the physical growth of urban areas, be it horizontal or vertical. According to the UN, in 2007 more than 50% of the world population were living in cities for the first time in human history. According to predictions probably two third of the world’s population will live in cities by the year 2030.
In some parts of the world, globalization has immensely promoted local economy and consequently the construction of tall buildings. The City of Shenzhen, China, for example, was a small fishing village in the 1970s. Because of global forces and rapid foreign investment, it was transformed to a modern city of skyscrapers. (..) It now is reputedly one of the fastest growing cities in the world (…). Shenzhen´s population has increased from 30.000 to more than 13 million during the last two decades.
2017 UN statistics show, the populations of cities has been growing tremendously in the last decades. The number of megacities (ed. with a population of 10 million or more people) grew from nine in 1985, to 19 in 2004, to 25 in 2010. In 2018, the number of megacities reached 37. UN predicts that the number of megacities will rise to 41 by the year 2030.
In 2018, an estimated 55.3 per cent of the world’s population lived in urban settlements. By 2030, urban areas are projected to house 60 per cent of people globally and one in every three people will live in cities with at least half a million inhabitants.The World’s Cities in 2018, United Nations Data Booklet
As Megacities today are a reality and giga cities soon will be, one of the main issues in the discourse on Megacities is its definition. The term ‘Megacities’ “has already generated much debate involving not only questions about its physical aspects of territorial size, population and density but also considerations about its system of governance and organization.”Interestingly, in Hall’s opinion the concept of a Megacity is not defined by the size of its population or the size of its spatial territories but by the agglomeration of functions and networks. “A Megacity is therefore a concept that is imposed on a particular urban agglomeration which consists of a number of networked metropolitan cores and which usually houses a large number of populations and covers a vast spatial territory”.
Although the growth of Megacities can be varied with respect to location (US vs. Europe vs. Asia Pacific) and population settings , “the central concept remains the same: the underpinning role of infrastructure which allows, encourages and makes possible these regional megacity arrangements. The story of the rise and the decline of a Megacity is very much determined by the conditions of its supporting infrastructures” .
|Industrial-age centralized cities||Demographic change||Population flood primate cities||Growth of primate cities|
|Decentralized suburban communities||Economic restructuring||Incorporation of low density rural spaces||Migration|
|Vast urban continuum (consumption services, new economic production hubs – Edge Cities and |
|Distributed central place systems||Too few jobs||Mass production|
|Centres absorbed into expanded urban space||High density of peripheral slums||Manufacture in-led export development|
|Globalization of trade and technology|
Field of controversy: Infrastructure and social sustainability
As we are facing ongoing advancements in information as well as transportation technology, infrastructure already has and will also play one of the most important factors when it comes to city planning in the near future. According to Kingsley E. Haynes , infrastructure is the glue of Megacities. It is about “the availability of transportation, ICT infrastructure and a general spatial quality that attracts highly education workers certainly do contribute to economic development” . But it’s not just about infrastructure providing transportation and mobility opportunities.
Nowadays people are facing a growing complexity coming along with technologic innovations and the need of being permanently connected to manage work and life. With the given surroundings they increasingly lack opportunities to escape into private spaces. Thus Rogers recommends to put emphasis on social harmony as well: „Especially the quality of public space where people from all kind of backgrounds can meet and interact is crucial“ .
Following this, the examination of cities will also lead to a discussion about (social) sustainability. Cities perceived as sustainable are often linked with the offer of sufficient open or community spaces as well as natural, green areas. Compact urban living can be seen as one possibility to provide social and ecological spaces. Thus, the concept of “density is viewed as a tool to create a more sustainable city. Many planners or, for example the Urban Land Institutes on the United States, are supporting this view: By strategically increasing the number of dwelling units per acre, cities not only will go a long way towards meeting their sustainability objectives, but will also be competitive, resilient and great places to live.”
But this is not happening in most of the existing mega cities. Looking especially at cities in eastern countries, overpopulated slums are constantly growing. As a result, space in cities is no longer affordable for low-income workers. These settlements or city districts have problems with unsanitary situations and missing health care, which leaves these inhabtiants with the lack of essential basic living conditions. The United Nation Human Settlements Program defines a slum settlement as a „household that cannot provide one of the following basic living characteristics:
- Durable housing of a permanent nature that protects against extreme climate conditions
- Sufficient living space, which means not more than three people sharing the same room
- Easy access to safe water in sufficient amounts at an affordable price
- Access to adequate sanitation in the form of a private or public toilet shared by a reasonable number of people
- Security of tenure that prevents forced evictions” (via Thoughtco.com).
Cities influence people’s life(-styles)
The main focus in urban planning seems the search of answers to questions like: How to meet citizens’ expectations in the future when we are facing Gigacities? Is it possible to ensure social interactions through architecture and if so, how? Is it inevitable that megacities will be fostering growth decentralisation, fragmentation of urban spaces and above all the occupation of continuous urban space by very large populations as Gottmann and Berry  have observed? As cities are providing increasingly more opportunities, the importance of urban development should be based in the consideration of human needs of personality, warmth, intimacy and social interaction. Cities bring together education, transportation, energy systems, public security and amenities of urban life in addition to employment opportunities that draw people from rural areas. In other words:
“Adherence to a certain life style (individuality, mobility, global orientation, etc) is a core feature of an urbanized world. This draws the conventional focus of urban planning away from the urban–rural divide towards mobility, connection and lifestyles. Any urban way of life has to be supported by a proper set of values, cultural behaviours and infrastructures acting as determinates of an urban culture for residents and business.”Peter Nijkamp: Megacities – Lands of Hope and Glory 
If sustainable cities offer zones of interaction through public spaces, it is also important to look at the degree of privacy a city can ensure to its inhabitants. Private spheres are closely associated with the social unit of a household. Privacy is expressed as a feeling of exclusivity and intimacy and find its ultimate value in the modern family house. Over time this private sphere has been perceived more or less as a centre of sociability and a safe haven from impersonal urban world. This contrast brings the interdependence of interiority and exteriority into examination. Beatriz Colomina describes interiority as a horizon defining an enclosure by marking a limit to the space of what can be seen .
Inside the house, a hierarchical stratification was created […]. This hierarchy was reflected in the transformation of the house from one dominated by a multifunctional large hall to a multiplication and specialization of rooms connected through corridors, in a sense using an urban morphology for domestic space. These introduced a range of private, semi-private, and even semi-public spaces around the house to cater for a co-existence of individual, personal private space and household interpersonal spaces. Stratification coincided with a differentiation of house types, from the townhouse to the terraced, semi-detached- detached houses and flats, reflecting the new social hierarchies. These characteristics of the domestic space were extended to larger sections of society through state intervention, by mass public housing schemes, and through the market mechanism of speculative volume building. 
As the world and above all, cities, grow in population, architects and city planners increasingly  have to face a lack of space for their inhabitants. Take China for instance, where statistics forecast a migration of over 350 million people from rural to an urban environment by 2025 . This challenge is fostering high-rise development. In addition, this development is supported by raising land prices serving as another key driver for vertical construction. Building vertical will consequently lead to higher buildings and – in consideration with their height and scale – inevitably have a huge impact on the buildings’ location and surroundings. The efficiency of skyscrapers can be demonstrated at the world´s tallest public housing building: the Pinnacle Duxton in Singapore. Completed in 2009 this major public housing project consists of seven 50-story connected towers. It consists of a total of 1,848 units comprised of 35 different unit design variations.  In comparison to a 500-unit single–family subdivision, skyscrapers do not require lots of roads, sidewalks, sewers, hydro lines, power and gas lines, light standards, etc.
different efforts to mass housing, the challenge in city planning becomes
obvious: Architects have to enhance the relationship between high-rises and the
environment inside a city.
“Many of the major advantages of tall buildings mirror images of their potential drawbacks. For example, tall buildings make efficient use of costly land, but doing so may create a race in pumping up land prices. Increased height provides tenants with spectacular views of the city. However, increased height can also induce phobias associated with living in high floors. Further, tall buildings enjoy low-energy vertical transportation; however, such form for transportation takes away space from the building and could also discourage walking. Tall buildings promote compact and efficient development, but may cause overcrowding and congestion.”
Since decades, architects have been seeking for sustainable approaches in urban living and share their visions of urban planning in an attempt to identify potential solutions for controversies, attached to Mega-cities. The idea of future-cities and the search for a perfect-ideal-city goes a long way back. “First described as a fictional island society in Greece by Sir Thomas More in 1516, the word ‘utopia’ has evolved to mean any community with a visionary system of political and societal perfection—cities that function to improve the daily lives of their citizens. Worth mentioning is the neoclassical architecture of Claude-Nicolas Ledoux who published his idea of a perfect city around 1800 with his visionary plan for the Ideal City of Chaux.
Densification: Vertical city center
Later – in the 1920s and 1930s – Le Corbusier brought urban development in his interest in theoretical studies and experimented with a series of highly utopian urban planning concepts. He approached urbanisation from an idealistic and somehow moralistic point of view: “Modern industry has disrupted old relationships and has brought about despair and a dangerous crisis. But fortunately, the very same modern industry and our new technology that have caused this disruption at the same time offer the possibility of a solution and liberation. New construction methods, which have revolutionized architecture, provide the means for a new organization of cities,” claims Le Corbusier . His vision of reconstruction the center of Paris, the so-called Plan Voisin of 1925, is well known, “an idealistic mega-project that called for the bulldozing of central Paris and replacing it with monolithic 60-story towers set within an organised street grid and ample green space.” In Corbusier’s opinion, the city centre has a tendency to become denser and more congested. To avoid horizontal growth toward the periphery, increase land value and simultaneously the value of skyscrapers, “he recommends both densification and reduction of the diameter of the center as well as the whole city” .
He believed the efficient plan could transform society by raising the standard of living for all socioeconomic levels. However, his concept was rejected as it fosters divided housing based on class .
Low-density development emphasizing suburban life
In the 1930s, Frank Lloyd Wright published an ideal vision of the city called “Broadacre City” which is completely contrary to that of Le Corbusier. While Le Corbusier and many other utopian visions approached the concept of density, Frank Lloyd Wright rejected urban areas altogether and thus can be seen as “complete antithesis of Le Corbusier’s ideal cities. Broadacre championed low-density development centered around automobile transit, where all amenities could be easily accessed within a radius of 150 miles” .
Believing in the individual, Wright envisaged each house to be set in about an acre of land, providing its inhabitants with gardening space to grow their own food and be absolutely autonomous. Further, Wright’s vision anticipated major advances in infrastructure: “Wright detailed plans for spacious landscaped highways, beautifully designed public service stations, roadside markets, garden schools, and parks, which were integrated to foster self-improvement and maximize enjoyment,” analyses James Bartolacci at Architizer.
“Imagine spacious landscaped highways, giant roads, themselves great architecture, pass public service stations, no longer eyesores, expanded to include all kinds of service and comfort. They unite and separate — separate and unite the series of diversified units, the farm units, the factory units, the roadside markets, the garden schools, the dwelling places (each on its acre of individually adorned and cultivated ground), the places for pleasure and leisure. All of these units so arranged and so integrated that each citizen of the future will have all forms of production, distribution, self improvement, enjoyment, within a radius of a hundred and fifty miles of his home.”Frank Lloyd Wright – The Disappearing City
From utopia in the past to reality in the present
Although the utopian concepts of the early twentieth century remain utopias and above all idealistic, wishful thinking, it can be stated that both concepts at a certain degree are comparable with today’s mega cities. In fact “Wright’s utopian city did not anticipate today’s widespread problems of suburban sprawl and the environmental degradation that comes from the basic principles of Broadacre.” Nevertheless Frank Lloyd Wright’s concept of de-urbanisation and horizontal growth shows similarities with the suburban arrangements in the United States. Seeking instead for Le Corbusier’s utopian approach in present architecture, is not surprising that the Swiss-French architect ventured frustrated outside Europe to spread his ideas as his Plan Voisin was rejected in France. And even today, his vision could not be imagined as a role model for European cities. Nevertheless, looking at city development in Asia or in South America, it becomes obvious that the concept of city densification is already a reality here – in an exaggerated version.
Hong Kong as example, is one of the richest cities in the world with a population of seven million inhabitants which means 6,544 people per sq km (total land mass: 1104 sq km). The city is one of the densest populated regions in the world. It is also one of the world’s leading international financial centres, has the world’s second busiest container port and the world’s busiest airport for international cargo. Hong Kong’s transportation network has to manage over 11 million commuters per day. The region serves as major business hub attracting people from all classes in an expection of better job opportunities and better living conditions. This is reflected within the city’s massive population growth over time: “Hong Kong’s population in 1950 was 2.2 million. By 2001, it increased to 6.7 million, which means the population increased more than 3 times in size. […] Hong Kong’s population is expected to reach 8.469 million by 2041.”
This development has lead to the challenge of finding space to house all these people. Although Hong Kong covers 1104 sq km land, only around 20 per cent is buildable. This has forced the government of Hong Kong, city planners and architects to grow, and hence build, vertically. As the value of land lies approximately at US$ 30,000 per square meters, developers maximize the site and design buildings between 50 and 80 floors. In 2014, Hong Kong counts 2,354 high-rises above 100m from which 295 exceed a height of 150 metres which puts the city at the top of world rankings as it has more buildings higher than 500 feet (150m) than any other city.
As BBC reports, the extreme population conditions quicken systemic poverty. It’s not surprising that one-sixth of the population in 2005 lived in shanty towns. “In Hong Kong the rent per square foot per month is about 90 dollars, because of the too long public housing waiting list and therefore, many people are forced to make a home in a very small space“ .
Thousands of unemployed citizens live in caged homes or wood-partitioned cubicles. Other low-income families squeeze for example in tiny one-room cubic apartments which are sometimes no larger than four to seven feet.[ In other words: The bunk bed is built above or next to cooking areas and food storage which is located just inches away from electronics. The director of design of human health at Boston Architectural College, Dak Kopec, states that micro-apartments, due to their compact design, force residents to rearrange living quarters all day long.
According to the Society for Community Organization (SoCO), a Chinese Human Rights Group, “an estimated number of 100,000 people are living in unauthorized apartments in the city, a number that may well be low. In recent years, there are a huge number of partitioned rooms being built in industrial buildings […]. As it is illegal to live there, those residents living at industrial buildings are not counted and hence the government figure is underestimated.”
Besides the circumstance of living illegally, life in such cubicles puts forward further issues: Tiny one-room cubic apartments combined with a group of dwellers means not only a lack of space but also a lack of privacy. “In these situations, modern amenities—such as floor to ceiling windows, extra storage and a communal roof deck— won’t compensate for a fundamental lack of privacy […].” Sharing one room with four or more people is a deep break in terms of privacy. The boundaries between people melt into each other and individuality is lost. Beyond the economic impact of smaller spaces, our homes also serve an important role in communicating our values and goals, or what scientists call ‘identity claims’.” In the chapter above, social interaction as a desirable goal to be ensured by an architect is referred to. With respect to the one-room cubic apartments in megacities such as Hong Kong, the level of interaction and the interpersonal relationships are carried to the extremes. Being social is not voluntary anymore. In fact, the interactive part forces itself upon the people living huddled in these small spaces. Samuel Gosling, a psychology professor at the University of Texas, studies the connection between people and their possessions. He is of the opinion that “when we think about micro-living, we have a tendency to focus on functional things, like is there enough room for the fridge […]. But an apartment has to fill other psychological needs as well, such as self-expression and relaxation that might not be as easily met in a highly cramped space.”
With such a big change
of privacy, one may wonder why people still migrate to cities. Although it is a
move from rural poverty into urban poverty, it may not necessarily be a move
into a brighter future. It can be seen as sign of
resignation that more and more people in Hong Kong are coping with living in such
shrinking spaces understandably. But, a home should ideally not only be governed
monetarily, but also provide room for development, relaxation and comfort from
the external urban life.
As depopulation indicates, there seems to be no way out of vertical (high-rise construction) or horizontal growth (take over off suburbs). As population permanently rises, we have to find a solution to counteract the resulting lack of space. Looking at cities in developing countries such as Hong Kong, the dimension of dwelling problems gets clearer, and it is obviously not just the unaffordability of space, but larger paradigms in question.
As unemployment or delinquency are one of the main issues in urban planning, architects and engineers have to face these challenges when they want to build sustainable cities. But what could be a potential start point for problem-solving? Lee suggests that “housing design itself can play an important part in alleviating the adverse effects of high-density living” . He argues that considerations should shift away from an architecture-centric point of view towards a systematically assessed approach encouraged by social science studies so that buildings may be designed in a way that minimizes negative effects of high-density living while maximizing the positive effects on society at large .
The Hong Kong architect, Gary Chang attempted to maximize the potential of small apartments. Searching for an optimized prototype of a flat, he redesigned a 32 sq m micro apartment consisting of three small bedrooms, a kitchen and a bathroom. Since he used to live there with five other family members he slept in the hallway, so they could rent the third bedroom. He studied different variations, 24 in total, by moving the walls into different positions and introduced sliding and built-in folding furniture. With this alterable space he could include the kitchen, bath as well as dinning- and bedroom.[
It needs to be considered that such projects are usually very expensive. Thus, most of the time, redesigning small spaces comes with a cost factor enabling most people to continue living in the default small spaces.
From a macro perspective, cost play an important role in the funding of social housing projects by governments as well. As there is usually insufficient capital, many funded buildings have been build up fast and cheap and thus are not very habitable and comfortable. From a long-term point of view it becomes obvious that planning of such housing projects – although planned by the architects or urban planners – are not well-elaborated as the results have not been accepted by the residents. Prior imagined green spaces remain unused and become dilapidated. The intention and results are divergent. David Sim, Partner at Gehl Architects, sees the cause of misguided urban planning in an architectural approach being not conducive:
There is this very difficult tradition, which comes from the way we teach architecture and planning. It´s the idea, that one person can solve everything. We even have this term ‘the master plan’. I’m going to do the master plan, which will answer all questions. Is it possible? Cities are unbelievably complex. Even the idea of a master plan is really crazy. All we can do is make a framework, a very robust framework, which allows life to take place. One thing I can be sure about is that in 10 years, 20 years, 50 years and 100 years human being will be more or less the same. Our senses will work more or less the same way. We´ll probably enjoy meeting each other in the same way we enjoy it today. […] I don´t think we can plan these things or by me drawing a line that I can make things happen. I can´t force anybody to do anything or be anyone but we can make invitations.”The Human Scale
Urban future requires a radical new thinking. Perhaps we could focus on ways to create cities that offer a more healthy and even pleasant life for their citizens, because one of the main problems is that “the implications for the health and social well-being of the people living under the conditions of high density […] have not been systematically assessed. The government and funding agencies should, therefore, encourage social science studies of these matters.”
In addition, they could emphasize on enforcing housing offers that are attractive to different classes. “When policies and planning come from the top, they never understand the very aspiration of the people. […] If you don’t encompass everybody in your planning and understanding of transportation and housing, you are heading towards a chaos created by yourself.” This could foster gentrification and as it can be seen in the prosperous development of urbanization in the western world could be one way out of the current situation in high-density cities such as Hong Kong. Following the goal to change people’s lives in cities to the better, a strategy must be found that includes active citizen participation, invites their voice in the decision-making processes and gives them the opportunity of contribution. This may be a positive way to strengthen people’s identification with their surroundings.
Idealistic or utopian approaches have always intrigued philosophers, architects and artists since antiquity, but these have largely remained only utopias. The migration of people towards cities is nothing new. The Industrialisation in Europe faced a similar problem at a much smaller scale than the Asian and South American cities facing now. However, in spite of their differing reasons for the shift, the most important aspect for a relatively successful approach will be a holistic planning that includes social factors and, above all, people from all classes.
 B. Ladd (2008): Autophobia. Love and Hate in the Automotive Age. University Of Chicago Press, p. 96.
 Hall, P. (2010): Megacities, World Cities and Global Cities. In: Buijs, S.; Tan, W. & Tunas, D. (2010): Megacities. Exploring a Sustainable Future. 010 Publishers, p. 77.
 See e.g. (1) Garreau, J. (1991): Edge City: Life On The New Frontier, New York. Doubleday. Or (2) Hall, P. & Pain, K. (2006): The Polycentric Metropolis. Learning from Mega-City Region in Europe. London: Earthscan.
 Hall, P. (2010): Megacities, World Cities and Global Cities. In: Buijs, S.; Tan, W. & Tunas, D. (2010): Megacities. Exploring A Sustainable Future. 010 Publishers, p. 79.
 Haynes, K.E. (2010): Infrastructure. The Glue Of Megacities. In: Buijs, S.; Tan, W. & Tunas, D. (2010): Megacities. Exploring A Sustainable Future. 010 Publishers, p. 93.
 Buijs, S.; Tan, W. & Tunas, D. (2010): Lesson learnt. In: Buijs, S.; Tan, W. & Tunas, D. (2010): Megacities. Exploring A Sustainable Future. 010 Publishers, p. 26.
 Haynes, K.E. (2010): Infrastructure. The Glue Of Megacities. In: Buijs, S.; Tan, W. & Tunas, D. (2010): Megacities. Exploring A Sustainable Future. 010 Publishers, p. 93.
 Nijkamp, P. (2010): Megacities. Lands Of Hope And Glory. In: Buijs, S.; Tan, W. & Tunas, D. (2010): Megacities. Exploring A Sustainable Future. 010 Publishers, p. 101.
 Colomina, B, Battle Lines; Interstices 4, p.1.
 Public and Private Spaces of the City By Ali Madanipou p.202-203.
 To read more see the research of architects, visonaries and urbanists like Le Corbusier, Edmund Bacon and William Holly Whyte who propagated the significance of increasing densities and vertical scale cities from an historical point of view: Kheir Al-Kodmany ,K. ; Ali M (2013): The Future of the City: Tall Buildings and Urban Design. WIT Press, p.3.
 Kheir Al-Kodmany ,K. ; Ali M (2013): The Future of the City: Tall Buildings and Urban Design. WIT Press, p.31.
 Pinnacel Duxton offical URL: http://www.pinnacleduxton.com.sg/about.php#unique , 2014-03-20.
 Teige, K. (2002): The Minimum Dwelling. MIT Press. p.143-144.
 Teige, K. (2002): The Minimum Dwelling. MIT Press. p. 144.
 See Teige, K. (2002): The Minimum Dwelling. MIT Press. p. 144.
 Ingersoll, R. (2006): Sprawltown. Looking for the City on Its Edges. Princeton Architectural Press. p. 140.
 Dwelling in Cages- Poor Communities Living in Hong Kong. URL.
 Lee, R.P.L. (1981): High-Density Effects in Urban Areas. What Do We Know and What Should We Do? In: Lee, R.P.L.: Social Life and Development in Hong Kong. Chinese University Press. p.19.
 see Lee, R.P.L. (1981): High-Density Effects in Urban Areas. What Do We Know and What Should We Do? In: Lee, R.P.L.: Social Life and Development in Hong Kong. Chinese University Press. p.19.