Lincoln, W. Bruce
Anchor Books, 1987
Buku Teks
edited by Henry Steele Commager
Appleton-Century-Crofts, 1949
Buku Referensi
by Albert P. Blaustein, Jay Sigler, Benjamin R. Beede, with Wayne E. Olson
Oceana Publications, 1977
Buku Referensi
selected by Henry Steele Commager
American Museum of Natural History, 1964
Buku Teks
edited by C.M.H. Clark
Angus & Robertson, 1955
Buku Teks