edited by Magie Toy
Academy Editions, 1995
Buku Teks
edited by Michael Banton
Tavistock Publications, 1972
Buku Teks
Greiner, Larry E.
Addison-Wesley Pub. Co., 1988
Buku Teks
Tracy, Diane
Pustaka Tangga , 1994
Buku Teks
Lenski, Gerhard Emman
McGraww-Hill, 1966
Buku Teks