Chaplin, J. P., author
RajaGrafindo Persada, 2006
Buku Referensi
Chaplin, J.P., author
Rajawali, 2011
Buku Referensi
S. Richard Sauber, Luciano L' Abate, Gerald R. Weeks, William L. Buchanan
Sage, 1993
Buku Referensi
de Vries, Louis, author
McGraw-Hill, 1951
Buku Referensi
London: Tiger Books International, 1994,
Buku Referensi