Cracolice, Mark S., author
Thomson, Brooks/Cole, 2007
Buku Teks
Russo, Steve, author
Pearson Benjamin Cummings, 2007
Buku Teks
Andrews, Donald H., author
McGraw-Hill , 1970
Buku Teks
Corwin, Charles H., author
Prentice-Hall, 2001
Buku Teks
Miller, G. Tyler (George Tyler), 1931-, author
Wadsworth, 1991
Buku Teks