Edson, Gary
Routledge, 1994
Buku Teks
Fopp, Michael A.
Routledge, 1997
Buku Referensi
edited by Michael Rines
Gower in Association with Marketing Magazine, 1981
Buku Teks
Skousen, Philip L.
McGraw-Hill, 2011
Buku Teks
editor-in-chief, Robert H. Bishop
CRC Press, 2002
Buku Referensi