Lenk, John D., author
McGraw-Hill, 1994
Buku Referensi
Prentiss, Stan
Prentice-Hall, 1979
Buku Teks
Lenk, John D., author
McGraw-Hill, 1991
Buku Teks
Cashmore, Ellis, author
Routledge, 1994
Buku Teks
Middleton, Robert Gordon, 1908-, author
Bombay: D.B. Taraporevala Sons & Private, 1972
Buku Teks