Yates, Christopher St. J.
Cassell Publisher, 1989
Buku Teks
Yates, Frank
Macmillan Publishing Co., 1981
Buku Teks
Damodaran, Aswath
Wharton School Publishing, 2008
Buku Teks
Frost, Frank J.
D.C Heath, 1980
Buku Teks
Wetherell, Margaret
Sage, 2002
Buku Teks