Chua, Beng Huat, and Edwards, Norman, Public space: design, use, and management, National University of Singapore, Centre for Advanced Studies, Singapore University Press, 1992, pp. 4-5.
Truy cập ngày 30 tháng 3 năm 2012. ^ Chua, Beng Huat, and Edwards, Norman, Public space: design, use, and management, National University of Singapore, Centre for Advanced Studies, Singapore University Press, 1992, pp. 4-5.