edited by Grace J. Kelleher
John Wiley & Sons, 1970
Buku Teks
Starling, Grover, author
Dorsey Press, 1979
Buku Teks
Hikmah Kurniaputri, author
Universitas Indonesia, 2017
UI - Tesis (Membership)
Vogel, Arthur I., author
The English Language Book Society, 1960
Buku Teks
Bierman, Harold, author
Richard D. Irwin, 1981
Buku Teks