Tuma, Nancy Brandon, author
Academic Press, 1984
Buku Teks
Lofland, John, author
Wadsworth, 1971
Buku Teks
Lofland, John, author
Wadsworth, 1984
Buku Teks
Bailey, Kenneth D., author
The free press, 1994
Buku Teks
Robson, Colin, author
Oxford, 2002
Buku Teks