edited by Linda Ellis
Garland Publishing, 1999
Buku Referensi
New York Garland 2000
Buku Referensi
Neustupny, Evzen
Cambridge University Press , 1993
Buku Teks SO
New York Harper and Brothers 1959
Buku Teks
Adkins, Lesley
Melbourne Cambridge University Press 1989
Buku Teks