Porteous, J. Douglas
Routledge , 1996
Buku Teks
Evans, Graham, author
Harvester Wheatsheaf, 1990
Buku Referensi
Steinfels, Peter
Simon and Schuster, 1980
Buku Teks
Mills, Stephen
Penguin Books, 1986
Buku Teks
Padover, Saul K. (Saul Kussiel), author
McGraw-Hill, 1960
Buku Teks