Levinson, David, author
New York: G.K. Hall & Company; 1996,
Buku Referensi
GK-Hall, 1994
Buku Teks
Hastings, James, author
T&T Clark, 1980
Buku Referensi
compiled and edited by C.A. Jacobson
Van Nostrand Reinhold, 1958
Buku Referensi
Pandey, A.K., author
Anmol Publications, 1992
Buku Referensi