Hodges, Luther H., author
Prentice-Hall, 1963
Buku Teks
Kilgannon, Pete, author
McGraw-Hill, 1980
Buku Teks
O`Shaughnessy, John, author
George Allen and Unwin, 1974
Buku Teks
Czinkota, Michael R., author
The Dryden Press, 1994
Buku Teks
Mason, R. Hal (Robert Hal), 1929-, author
John Wiley & Sons, 1981
Buku Teks