Hansen, Bertrand L., author
Prentice-Hall, 1960
Buku Teks
Yates, Frank
Macmillan Publishing Co., 1981
Buku Teks
Vanasse, Robert W., author
McGraw-Hill, 1976
Buku Teks
Purba, Sahala Manalsal, author
Fakultas Ekonomi dan Bisnis Universitas Indonesia, 1992
UI - Skripsi (Membership)
Guy, Dan M., author
John Wiley & Sons, 1994
Buku Teks