Mandell, Judy
John Wiley & Sons, Inc.q1996, 1996
Buku Teks
Rich, Carole, author
Wadsworth and Cengage Learning, 2010
Buku Teks
Block, Mervin, author
CQ Press, 2011
Buku Teks
Weeks, Edward, author
Writer`s Digest Books, 1962
Buku Teks
Hicks, Wynford, author
Routledge, 1995
Buku Teks