Morrison, Charles E., author
Martin Press, 1978
Buku Teks
Artikel Jurnal
Rosati, Jerel A., 1953-, author
Wadsworth, 2007
Buku Teks
Rosati, Jerel A., 1953-, author
Thomson, 2004
Buku Teks
edited by Robert W. Tucker, Charles B. Keely, and Linda Wrigley
Westview Press, 1990
Buku Teks