University of Illinois Press , 1967
Buku Teks
Fayerweather, John
McGraw-Hill , 1960
Buku Teks
Czinkota, Michael R., author
The Dryden Press, 1992
Buku Teks
Marcus, Edward, author
Pitman, 1965
Buku Teks
Rosenthal, Morris S., author
McGraw-Hill , 1950
Buku Teks