Morgan, Mary S., 1952-2011, author
Cambridge University Press, 2012
Buku Teks
Heshey, John, 1914-1993, author
McGraw-Hill, 2012
Buku Teks
Flesch, Rudolf, author
Harper & Brothetrs, 1960
Buku Teks
Zaltman, Gerald, author
Harvard Business School Press, 2003
Buku Teks
Rafe, Stephen C.
Harper Business, 1990
Buku Teks