Presser, Stephen B.
St.Paul, Minn., 1980
Buku Teks
Hall, Kermit L.
Oxford University Press, 1991
Buku Teks
Mashaw, Jerry L
Thomson/West, 2009
Buku Teks
Merryman, John Henry
Bobbs-Merril, 1978
Buku Teks
Schlesinger, Rudolf B.
The Foundation Press, 1950
Buku Teks