Edwards, Anne
Longman, 1996
Buku Teks SO
Walliman, Nicholas
Sage Publications Ltd , 2001
Buku Teks SO
Kellehear, Allen
Allen & Uwin, 1993
Buku Teks SO
edited by Jan Fook
Allen & Unwin, 1996
Buku Teks
Barzun, Jacques
Harcourt, Brace & World, 1970
Buku Teks SO