Boyan, Lee
Successful cold call selling
American Management Association, 1989
 eBooks
William, Miller
Knock your socks off prospecting: how to cold call, get qualified leads, and make more money
American Management Association, 2005
 eBooks
Roman, Murray
Telemarketing campaigns that work! / Murray Roman
McGraw-Hill, 1983
 Buku Teks
Walkup, Renee P.
Selling to anyone over the phone
American Management Association, 2006
 eBooks
Yarker, K.A.
International marketing
Business Books, 1976
 Buku Teks