edited by Sybil P. Parker
New York, McGraw-Hill
Buku Referensi
McGraw-Hill Publishing, 1989
Buku Referensi
Clayton, Jade
McGraw-Hill, 1998
Buku Referensi
Rosenberg, Jerry M.
John Wiley & Sons, 1993
Buku Referensi
Siegel, Joel G.
Macmillan, 1992
Buku Referensi