Drost, Pieter N., author
A.W. Sijthoff, 1951
Buku Teks
Drost, Pieter N., author
A.W. Sijthoff, 1965
Buku Teks
United Nations, 1988
Buku Teks
Carey, John, author
Oceana Publications, Inc, 1968
Buku Teks
Digumarti Bhaskara Rao
Discovery Publishing House, 2001
Buku Teks