Wortman, Camille B., author
Alfred A. knoff, 1985
Buku Teks
Wortman, Camille B., author
McGraw-Hill, 1992
Buku Teks
Rathus, Spencer A., author
Harcourt Brace College, 1993
Buku Teks
Wortman, Camille B., author
McGraw-Hill, 1999
Buku Teks
Wooldridge, S. W.
Hutchinson University Library,, 1970
Buku Teks