Vernon-Wortzel, Heidi, author
John Wiley & Sons, 1997
Buku Teks
prepared by Business International Corporation
Business International Corporation,, 1991
Buku Teks
Davidson, William H., author
John Wiley & Sons, 1982
Buku Teks
Vernon-Wortzel, Heidi, author
John Wiley & Sons, 1991
Buku Teks
Yip, George S., author
Prentice-Hall, 1995
Buku Teks