Allen, Peter
Selling
Pitman, 1998
Buku Teks SO
Robeson, James F.
Selling
Richard D. Irwin, 1978
Buku Teks SO
Panic selling
Artikel Jurnal
Wingate, John W.
Fundamentals of selling
South-Western Publishing, 1959
Buku Teks SO
Kurtz, David L.
Professional selling
Business Publications, 1982
Buku Teks SO