Ivey, Allen E.
Allyn and Bacon, 1996
Buku Teks
Pedersen, Paul
American Association for Counseling and Development, 1988
Buku Teks
Brammer, Robert
Thomson, 2004
Buku Teks
Brammer, Robert
Brooks/Cole Cengage Learning, 2012
Buku Teks
Pack-Brown, Sherlon P.
Sage, 2003
Buku Teks