Gross, Jean, author
Routledge: Taylor & Francis Group, 2008
Buku Teks
Lynch, James, author
World Bank, 1994
Buku Teks
Rakes, Thomas A., author
Allyn and Bacon, 1990
Buku Teks
Ysseldyke, James E., author
Corwin Press, 2006
Buku Teks
Mannix, Darlene, author
Jossey-Bass , 2009
Buku Teks