Le Roy, Michael K., author
Wadsworth, 2009
Buku Teks
Le Roy, Michael K., author
Wadsworth and Cengage Learning, 2013
Buku Teks
Johnson, Janet Buttolph, 1950-, author
CQ Press, 2012
Buku Teks
edited David Marsh and Gerry Stoker
Macmillan, 1995
Buku Teks
Pennings, Paul
Sage Publications, 1999
Buku Teks