American Psychological Association, 1985
Buku Teks SO
edited by G. Douglas Mayo
Memphis State University Press, 1979
Buku Teks
Sabaria Umahuk
Fakultas Psikologi Universitas Indonesia, 2006
UI - Tesis Membership
edited by Robert L. Linn ; sponsored jointly by National Council on Measurement in Education and American Council on Education
New York, 1989
Buku Teks
Crocker, Linda M.
Holt, Rinehart, and Winston, 1986
Buku Teks SO