Lancaster, Greoff, author
Crest, 2001
Buku Teks
McDaniel, Carl, author
South Western Cengage Learning, 2013
Buku Teks
Armstrong, Gary M., author
Prentice-Hall, 2005
Buku Teks
Farbey, A.D., author
Crest Publishing House, 2001
Buku Teks
Ryan, William T.
Richard D. Irwin, 1981
Buku Teks