Detail  population pyramid, rectangular-shaped 長方形の人口ピラミッド   chōhōkei no jinkō piramiddo rechteckförmige Bevölkerungspyramide Links Emily C. Chiu (2004): The One-Child Policy’s Socio-Demographic Impact - Current Trends and Alternative Policy Projections. http://undergrad.wharton.upenn.edu/research/scholars/volume1/Chiu-Chinss_One_Child_Policy.pdf