Sullivan, Dennis H., author
Richard D. Irwin, 1982
Buku Teks
edited by Willie Henderson, Tony Dudley-Evans and Roger Backhouse
Routledge, 1993
Buku Teks
Bingham, Robert C., author
McGraw-Hill, 1987
Buku Teks
Bingham, Robert C., author
McGraw-Hill, 1975
Buku Teks
Stengel, Donald N., author
Business Expert, 2011
Buku Teks