Current, Richard N., author
Alfred A. Knopf, 1965
Buku Teks
edited by Henry Steele Commager
Appleton-Century-Crofts, 1949
Buku Referensi
Graebner, Norman A., author
McGraw-Hill, 1975
Buku Teks
Bailey, Thomas Andrew, 1902-1983, author
D.C. Health, 1983
Buku Teks
Oscar Handlin ... [et.al] author
Belknap Press, 1963
Buku Teks