O`Donnell, Angela M., author
John Wiley & Sons, 2012
Buku Teks
editor, Eilean Hooper-Greenhill
Routledge, 1996
Buku Referensi
edited by Hans F. Crombag and Dato N. De Gruijter
Mouton, 1974
Buku Teks
Gage, N. L.
Houghton Miffiln, 1988
Buku Teks
Wardiman Djojonegoro, author
Ministry of Education and Culture , 1994
Buku Teks