Edward Arnold ,
Majalah, Jurnal, Buletin
Juhani Kesti, editor
IBFD, 2001
Buku Teks
edited by James E. Redden
Department of Linguistics Southern Illinois University, 1977/1978/1979
Buku Teks
Hughes, Arthur, 1941-
Cambridge University Press, 1994
Buku Teks SO
Davies, Alan, 1931 February 17-
Basil Blackwell, 1990
Buku Teks SO