Diamond, John L., author
Mattew Bender, 1996
Buku Teks
David A. Elder, author
Thomson, 2002
Buku Teks
Elder, David A.
Buku Teks
Jones, Michael A., author
Blackstone Press Limited, 2000
Buku Referensi
Statsky, William P., 1943-, author
Delmar Cengage Learning, 2012
Buku Teks