Vanty Triadha Rini
Universitas Indonesia, 2005
UI - Skripsi (Membership)
Dudek, Susan G.
J.B. Lippincott, 1997
Buku Teks
Karb, Virginia Burke
Mosby , 1996
Buku Teks
Aston, Elaine
Routledge, 1999
Buku Referensi
Bornatsky, I.
Foreign Languages, 1963
Buku Teks