Amstrong, John A.
Colombia University Press, 1963
Buku Teks
Kahin, George McTurnan
Cornell University Press, 1952
Buku Teks
Kahin, George McTurnan
Cornell University Press, 1952
Buku Teks
Kahin, George McTurnan
Cornell University Press , 1952
Buku Teks
Mclachlan, Noel
Penguin Book, 1989
Buku Teks