Dewis, M.
MacDonald and Evans, 1978
Buku Teks
Pheasant, Stephen
Macmillan, 1991
Buku Teks
edited by Marc J. Schabracq, Jacques A.M. Winnubst, Cary L. Cooper
John Wiley & Sons, 2003
Buku Teks
Golightley, Malcom
Learning matters Ltd., 2008
Buku Teks
Karban, Kate
UK Polity Press, 2011
Buku Teks