Adams, James Truslow
1946
Buku Referensi
editor Thomas C. Cochran, Wayne Andrew
Charles Scribner's Sons , 1962
Buku Referensi
U.S. Information Service,, 1981
Buku Teks
Current, Richard N.
Alfred A. Knopf, 1965
Buku Teks
edited by Henry Steele Commager
Appleton-Century-Crofts, 1949
Buku Referensi