Bell, Judith
Open University Press, 1993
Buku Teks
Walliman, Nicholas
Sage Publications Ltd , 2001
Buku Teks
Coghlan, David
Sage, 2001
Buku Teks
Briney, Kristin
Pelagic Publishing, 2015
Buku Teks
Magnusson, Eva
Cambridge University Press, 2015
Buku Teks