Westview Press, 1988
Buku Teks
Byman, Daniel, author
Cambridge University Press, 2007
Buku Teks
Colarik, Andrew M, author
IDEA Group, 2006
Buku Teks
Ariel Heryanto, author
Rouledge, 2006
Buku Teks
edited by Christopher C. Harmon, Andrew N. Pratt, Sebastian Gorka
McGraw-Hill, 2011
Buku Teks