Willey, Gordon R., author
Prentice-Hall, 1966
Buku Teks
Beal, Tim, author
Pluto Press, 2005
Buku Teks
Adams, Bradley J., author
Elsevier, 2012
Buku Teks
Howe, Hartley Edward
Facts on file, 1987
Buku Teks
edited by Suzanne McMahon; Miriam Palm; Pam Dunn
The Haworth Press, Inc., 1991
Buku Teks