Allen, Peter
Selling
Pitman, 1998
Buku Teks SO
Robeson, James F.
Selling
Richard D. Irwin , 1978
Buku Teks SO
Panic selling
Artikel Jurnal
Allen, Robert Y.
Selling dynamics
McGraw-Hill, 1984
Buku Teks SO
Wingate, John W.
Fundamentals of selling
South-Western Publishing, 1959
Buku Teks SO