Rosenwasser, David
Fort Worth Harcourt Brace College 1997,
Buku Referensi
Meyer, Michael, author
Little, Brown, 1982
Buku Teks
Eka Budianta, author
Jakarta : Pustaka Pembangunan, 1992
Buku Teks
Crepin, F
Nathan, 1988
Buku Teks
Hibbison, Eric
New Jersey Prentice Hall 1984,
Buku Referensi