Woodward, Ralph Lee, author
Oxford University Press , 1985
Buku Referensi
Westview Press , 1989
Buku Teks
Churchill, Anthony, author
The Johns Hopkins University , 1972
Buku Teks
The Law School of Harvard University, 1967
Buku Teks
Busey, James L., author
Random House, 1968
Buku Teks