Carroll, Stephen J.
Dorling Kindersley , 1992
Buku Referensi
Hardinge, Mervyn G.
Indonesia Publishing House, 2003
Buku Teks
F. A. Davis , 1996
Buku Teks SO
Hanson, Shirley May Harmon
F.A. Davis , 1996
Buku Teks SO
Koh, E.K.
Continental Press, 1988
Buku Teks