http://untappedcities.com/2013/08/09/the-beijing-that-never-was-a-two-center-beijing-under-the-1950-liang-chen-proposal/

http://www.chinahistoryforum.com/index.php?/topic/33298-father-of-modern-chinese-architecture/

http://en.wikipedia.org/wiki/Liang_Sicheng

http://15901625.blog.hexun.com/66789816_d.html