Schweitzer, Albert, author
Henry Holt, 1958
Buku Teks
Ziegler, David M., author
Little, Brown, 1981
Buku Teks
Ziegler, David M., author
Little, Brown, 1981
Buku Teks
Dixit, J.N. (Jyotindra Nath), 1936-2005, author
Routledge, 2002
Buku Teks
Lyon, Peter, author
Oxford University Press, 1969
Buku Teks