Kelly, Gary F.
Dushkin Pub, 1992
Buku Referensi
Kelly, Gary F.
The Dushkin Publishing Group, 1992
Buku Teks
Damisch, Hubert
MIT Press, 2000
Buku Teks
Sarabjot Singh, author
Management, Faculty of Economics, University of Indonesia and Philip Kotler Center, 2013
Artikel Jurnal
Ruzaimi Mat Rani, author
Words & Visuals Press Pte Ltd,
Buku Referensi