Neckers, Douglas C., author
John Wiley & Sons, 1977
Buku Teks
Morrison, Robert Thornton, author
Prentice-Hall, 1992
Buku Teks
Morrison, Robert Thornton, author
Allyn and Bacon, 1973
Buku Teks
McMurry, John, author
Brooks/Cole, 2007
Buku Teks
Weeks, Daniel P.
Saunders College , 1998
Buku Teks