Wilfried Marxer, editor
[, Springer], 2012
eBooks
Strauss, Anselm L., author
Sage, 1990.
Buku Teks
Tan, Joo Seng, author
McGraw-Hill , 2004
Buku Teks
Flora, David B., author
Sage, 2018
Buku Teks
Nancy Duxbury, W.F. Garrett-Petts, David MacLennan, editors
Routledge, 2015
Buku Teks