Peterson, L. K., author
Rockport, 2000
Buku Referensi
Peterson, L. K., author
Rockport Publishers, 2000
Buku Teks
Katz, Joel, author
N.J. : Wiley, 2012
Buku Teks
Lester, Paul Martin, author
Cengage Learning, 2014
Buku Teks
Rockport publishers, Inc., 2008
Buku Referensi