Angel, Myer
[publisher not identified], [date of publication not identified]
Buku Teks
Cohen, Morris R.
The Free Press , 1954
Buku Teks
Kogan, Nathan
Holt, Rinehart and Winston, 1964
Buku Teks
Diebold, John
D> Van Nostrand Company, Inc, 1952
Buku Teks
Myer, Rick A.
Brooks/Cole, 2000
Buku Teks