Pritchard, Peter.,
Oxford University Press, 1994
Buku Teks
Weiss, Donna
Jones & Bartlett Learning, 2014
Buku Teks SO
edit by Brenda Freshman, Louis Rubino, Yolanda (Linda) Reid Chassiakos
Jones and Bartlett, 2010
Buku Teks SO
Bruhn, John G.
Charles C. Thomas, 1993
Buku Teks
edited by Sarah G. Dean, Richard J. Siegert, William J. Taylor
Wiley-Blackwell, 2012
Buku Teks