Foris Publications, 1987
Buku Teks SO
Souvatzi, Stella G., 1966-
Cambridge University Press, 2008
Buku Teks SO
Massiah, Joycelin
United Nations Educational , 1983
Buku Teks
Rodenburg, Janet
KITLV , 1997
Buku Teks SO
Fifijanti Santoso
1995
UI - Tesis Membership