Fraser, David J., author
International Development Program of Australian and Colleges, 2006
Buku Referensi
Oxford University Press, 1978
Buku Teks
Lueck, William R.
University, 1932
Buku Teks
Higher School Pub. House, 1966
Buku Teks
Hill, L.A.
Longmans, Green and Co., 1959
Buku Teks