Potter, Joan
Kensington Publishing, 2002
Buku Teks
Patton, Sharon F.
Oxford University Press, 1998
Buku Teks
Institute for the Studies of Language and Cultyres of Asia and Africa, 2002
Majalah, Jurnal, Buletin
Williams, Ethel L.
Scholarly Resources Press, 1977
Buku Referensi
editor by Robert P. Holley
The Haworth Press , 1989
Buku Teks SO