Hickman, Ray, author
Macmillan, 1995
Buku Teks
Swisher, Linda
Mosby , 2010
Buku Teks
Krell, David Farrell, author
State University of New York Press, 1997
Buku Teks
McClintic, J. Robert, author
John Wiley & Sons, 1980
Buku Teks
Rohen, Johannes W., author
Lippincott Williams & Wilkins, 2011
Buku Referensi