Attenborough, David
BBC Worldwide Limited, 2004
Multimedia
Black, Kenneth
Prentice-Hall, 1994
Buku Teks
Mader, Sylvia S.
W.C. Brown , 1988
Buku Teks
Dyson, Freeman J.
Cambridge University Press, 1999
Buku Teks
Pough, F. Harvey
Prentice-Hall, 1999
Buku Teks