Roskin, Michael G., 1939-, author
Pearson Education, 2015
Buku Teks
Palmer, Monte, author
Thomson, 2006
Buku Teks
edited by George E. Delury
Facts on File, 1994
Buku Referensi
Christian Soe
McGraw-Hill, 2004
Buku Teks
Barringron, Lowell, author
Wadsworth and Cengage Learning, 2013
Buku Teks