Robbins, Stephen P., author
Prentice-Hall, 1998
Buku Teks
edited by Dinesch Bhugra
Routledge, 1996
Buku Teks
edited by Stephen A. Zeff and Thomas F. Keller
McGraw-Hill, 1973
Buku Teks
Sachs, Mendel, author
Open Court, 1988
Buku Teks
Bogart, Leo ed
Markham Company, 1969
Buku Teks