Thomlinson, Ralph
California State University, 1976
Buku Teks
Forrester, Jay W. (Jay Wright), author
Wright-Allen Press, 1973
Buku Teks
May, John F.
Springer, 2012
eBooks
Livi-Bacci, Massimo
Blackwell, 1997
Buku Teks
Chen, Kuan I., author
Bookman Associates, 1960
Buku Teks