Simons, Robert, author
Upper Saddle River Prentice Hall 1999,
Buku Teks
Burke, Barlow, Jr.
St. Paul, Minn, 1994
Buku Teks
Boyd, Harper W., Jr., author
Richard D. Irwin, 1958
Buku Teks
Ireland, R. Duane, author
South Western Cengage Learning, 2013
Buku Teks
Oxford University press, 2006
Buku Teks