Emerald Publishing Limited, 2019
eBooks
Cambridge University Press, 2015
Buku Teks
edited by Ann Lewis, Brahm Norwich
Open University Press, 2005
Buku Teks
Ysseldyke, James E., author
Corwin Press, 2006
Buku Teks
Rakes, Thomas A., author
Allyn and Bacon, 1990
Buku Teks