DiYanni, Robert
McGraw-Hill, 2000
Buku Teks SO
Kennedy, X.J.
HarperCollins, 1991
Buku Referensi
edited by Sylvan Barnet, Morton Berman, William Burto
Harper Collin College, 1992
Buku Teks
Kennedy, X.J.
HarperCollins, 1991
Buku Teks SO
Charters, Ann
Bedford/St. Martin`s, 1999
Buku Teks SO