Viotti, Paul R
Longman, 2012
Buku Teks
Olson, William Clinton, author
Prentice Hall International, 1994
Buku Teks
Williams, Howard
St.Maitin's Press, 1996
Buku Teks
Brown, Chris
Harvester Wheatsheaf, 1992
Buku Teks
Beitz, Charles R
Princeton University Press, 1979
Buku Teks