Friedrich, Carl J.
Frederick A. Praeger, 1962
Buku Teks
Barbu, Zevedei
Routledge , 1965
Buku Teks
Skidmore, Monique
ANU E Press, 2008
Buku Teks
McClosky, Herbert
McGraw-Hill, 1960
Buku Teks
Talmon, J.L. (Jacob Leib), 1916-
Frederick A. Praeger, 1961
Buku Teks