Smith, David
Macmillan, 1995
Buku Teks
Pusic, Eugen
Mouton, 1972
Buku Teks
Nina Rovinelli Heller, Alex Gitterman, editor
Routledge, 2011
Buku Teks
edited by Jerrold R. Brandell
Free Press, 1997
Buku Teks
National Association of Social of social Workers, 1980
Buku Teks