Sippl, Charles J.
Prentice-Hall, 1981
Buku Teks
Derfler, Frank J., author
Prentice-Hall, 1982
Buku Teks
Doll, Dixon R., author
John Wiley & Sons, 1978
Buku Teks
Housley, Trevor
Prentice-Hall, 1987
Buku Teks
Veith, Richard H., author
G.K. Hall, 1988
Buku Teks