Zito, George V., author
Human Science Press, 1979
Buku Teks
edited by Quentin H. Stanford
Oxford University Press, 1972
Buku Teks
American Association for the Advancement of Science, 1975
Buku Teks
Berelson, Bernard, author
The Population Council, 1975
Buku Teks
edited by Mindel C. Sheps and Jeanne Clare Ridley
University of Pittsburgh Press, 1965
Buku Teks