Artikel Jurnal
Chen, Xiao, author
China Intercontinental Press, 2006
Buku Teks
Zhang, Xueying, author
Foreign Languages Press, 2009
Buku Teks
Fisher, Gene H.
N.Y. American Elseview , 1971
Buku Teks
Hutchins, Robert M.
Center for the study of Democratic Institutions, 1963
Buku Teks