Iacobucci, Dawn
John Wiley , 2001
Buku Teks
Reedy, Joel, author
The Dryden Press, 2000
Buku Teks
Brannan, Tom, author
Crest Publishing House, 2001
Buku Teks
Still, Richard R.
Prentice-Hall, 1988
Buku Teks
edited by Reavis Cox and Wroe Alderson
Richard D. Irwin, 1950
Buku Teks