Kearns, Francis E.
Holt, Rinehart and Winston, 1970
Buku Teks
Connolly, Paul H.
Harper & Row, Publisher, 1981
Buku Teks
Decker, Randall E.
Little, Brown And Company, 1980
Buku Teks
Greenberg, Florence Bonzer, author
The Bobbs-Merrill, 1967
Buku Teks
Steven, Laurence, author
Prentice-Hall, 1999
Buku Teks