Christoper, Tom, author
Free Press, 1982
Buku Teks
Weber, Janet, author
J.B. Lippincott, 2001
Buku Teks
Kochar, Mahendr S.
Springer , 1985
Buku Teks
Porche, Demetrius James, author
Jones and Bartlett Learning, 2012
Buku Teks
Bond, John
Churchill Livinstone , 1994
Buku Teks