Johnson, John M., author
The Free Press, 1975
Buku Teks SO
edited by Geoffrey Walford
Falmer Press, 1998
Buku Teks
McLeod, John, author
Sage Publications , 2003
Buku Teks
Molly Andrews, Corinne Squire, Maria Tamboukou, editor
Sage, 2009
Buku Teks
Silverman, David, author
Buku Teks