Omrod, Jeanne Ellis, author
Pearson Education, Inc., 2009
Buku Teks
Arends, Richard I., 1990-, author
McGraw-Hill, 2012
Buku Teks
Schwartz, Barry, author
W.W. Norton, 1991
Buku Teks
Lutz, John, author
Waveland Press, 2005
Buku Teks
Leahey, Thomas Hardy, author
New Jersey, 2000
Buku Teks