Bremer, Kare
Timber Press, 1994
Buku Teks
Rela Febriani, author
2016
UI - Skripsi (Membership)
Febrini Cesarina, author
Universitas Indonesia, 2008
UI - Skripsi (Open)
Humphries, Christopher J., author
Clarendon Press, 1986
Buku Teks
Scott-Ram, N.R.
Cambridge University Press, 1989
Buku Teks