Allen, Peter
Selling
Pitman, 1998
Buku Teks SO
Allen, Robert Y.
Selling dynamics
McGraw-Hill, 1984
Buku Teks SO
Wingate, John W.
Fundamentals of selling
South-Western Publishing, 1959
Buku Teks SO
Kurtz, David L.
Professional selling
Business Publications, 1982
Buku Teks SO
Sutton, Kelso
The technique of selling
McGraw-Hill, 1949
Buku Teks SO