Burton, Lorelle
John Wiley & Sons Australia, 2009
Buku Teks
Baron, Robert A.
Simon & Schuster, 1992
Buku Teks
Gray, Peter
Worth Publishers, 1999
Buku Teks
Ciccarelli, Saundra K.
Pearson - Prentice Hall, 2006
Buku Teks
Ciccarelli, Saundra K.
Pearson Prentice Hall, 2006
Buku Teks