McMenemy, David, author
Facet, 2006
Buku Referensi
Liu, Jia, author
Chandos Publishing, 2007
Buku Teks
McClure, Charles R., author
[American Management Association;, ], 2009
eBooks
Ziarnik, Natalie Reif, author
American Library Association, 2003
eBooks
Rowley, Jennifer, author
Clive Bingley , 1980
Buku Teks