Crang, Mike, author
Routledge, 1998
Buku Teks
Kaplan, David, author
John Wiley & Sons, 2009
Buku Teks
Kendall, Henry M., author
Harcourt, Brace, 1958
Buku Teks
Petersen, James F., author
Brooks/Cole Cengage Learning, 2012
Buku Teks
Malinowski, Jon C., author
McGraw-Hill, 2012
Buku Teks