edited by Frank S. Barnes and Ben Greenebaum
CRC Press, Taylor & Francis, 2007
Buku Referensi
Bahill, A. Terry
Prentice-Hall, 1981
Buku Teks
edited by K.G. Das
John Wiley & Sons, 1983
Buku Teks
edited by Lise Jouanin, Catherine Lapierre
Elsevier Academic Press, 2012
Buku Teks
edited by Michael Rines
Gower in Association with Marketing Magazine, 1981
Buku Teks