Yale University Press, 1967
Buku Teks
Todd, Lewis Paul
Harcourt Brace Jovanovich, 1986
Buku Teks
edited by Robert Clayton Pierce
Thomson Learning, 2001
Buku Teks
Abel, Darrel, author
Barron's Educational Series, 1963
Buku Referensi
Hughes, Robert, author
Alfred A. Knopf, 1997
Buku Teks