Creanor, L.
University of Glasgow , 1995
Buku Teks
Open University Press, 1997
Buku Teks
Ngan Hoe, Lee, Dawn, Ng Kit Ee, editors
World Scientific, 2015
Buku Teks
Myint Swe Khine, editor
Springer, 2012
eBooks
Chastain, Kenneth
Rand McNally , 1971
Buku Teks