Glaser, Barney G., author
Aldine, 1967
Buku Teks
Strauss, Anselm L., author
Sage, 1990.
Buku Teks
Bryant, Antony, author
Oxford University Press, 2017
eBooks
Strauss, Anselm L., author
Sage, 1998
Buku Teks
Marshall, Catherine, author
Sage, 1999
Buku Teks