Buku Teks
White, James J., author
St. Paul, Minn, 1995
Buku Teks
Reed, Edward Wilson, 1913-, author
Prentice-Hall, 1989
Buku Teks
Bradgate, Robert, author
Butterworth, 1991
Buku Teks
Simpson, Laurence P., author
Alexander Hamilton Institute, 1961
Buku Teks