The Direct marketing handbook
Edward L. Nash, editor in chief
McGraw-Hill , 1992
Buku Referensi
Roberts, Mary Lou
Direct marketing management
Prentice-Hall, 1989
Buku Teks
Nash, Edward L.
Direct marketing : strategy, planning, execution
McGraw-Hill, 1986
Buku Teks
Stone, Bob
Successful direct marketing methods : interactive, database, and customer-based marketing for digital age
McGraw-Hill, 2008
Buku Teks
Nickels, William G.
Marketing communications and promotion
Grid, INC , 1976
Buku Teks