Foresman, Galen A., author
Wiley Blackwell, 2017
Buku Teks
Brudney, Kent M., author
Thomson, 2003
Buku Teks
Smith-Stoner, Marilyn, author
Lippincott, 1999
Buku Teks
Paul, Richard W.
Prentice-Hall, 2002
Buku Teks
Paul, Richard W., author
Hawker Brownlow Education, 1993
Buku Teks