Speziale, Helen J. Streubert
J.B. Lippincott, 1999
Buku Teks SO
Valiga, Theresa M.
Springer, 1991
Buku Teks SO
edited by Alan Bryman, Robert G. Burgess
SAGE Publication, 1999
Buku Teks SO
Holloway, Immy
Blackwell, 1997
Buku Teks
edited by Mauthner, Melanie (ed); Birch, Maxine; Jessop, Julie; Miller, Tina
Sage, 1002
Buku Teks SO