Mason, Diana J.
Saunders Elsevier, 2002
Buku Teks
edited by Diana J. Mason, Judith K Leavitt, Mary W. Chaffeee
Elsevier Saunder, 2012
Buku Teks
Foss, Mark
Prentice-Hall, 2000
Buku Teks SO
Edward Arnold , 1994
Buku Teks SO
Barker, Carol
Sage Publications, 1996
Buku Teks