Perloff, William H.
John Wiley & Sons, 1976
Buku Teks
Krynine, Dimitri P.
McGraw-Hill, 1947
Buku Teks
Craig, R.F. (Robert F.)
Chapman & Hall , 1992
Buku Teks
Lambe, T. William
John Wiley & Sons, 1969
Buku Teks
Craig, R.F. (Robert F.)
Van Nostrand Rheinhold, 1974
Buku Teks