Lewis, Marcia A.
F.A. Davis Company, 2012
Buku Teks
Garrison, Marsha, author
Thomson/West, 2009
Buku Teks
West Publishing Co, 1987
Buku Teks
Hammaker, Donna, author
Delmar Cengage Learning, 2011
Buku Teks
Blackman, Norman S., author
Harwood Academic Publishers, 1990
Buku Referensi