Nababan, Betty Weri Yolanda, author
2016
UI - Tesis (Membership)
The Stationery Office, 1999
Buku Teks
Richards, Denis, author
Longman, Green, 1952
Buku Teks
Chapman, Richard A., author
Constable, 1970
Buku Teks
Gilliat-Ray, Sophie, author
Cambridge University Press, 2010
Buku Teks