Perosa, Sergio
New York University Press, 1985
Buku Teks
selected by Henry Steele Commager
American Museum of Natural History, 1964
Buku Teks
Cohn, Ruby
Macmillan, 1991
Buku Teks
Nannes, Caspar H,
The Catholic University, 1960
Buku Teks
Hoffman, Frederick J.
The Free Press, 1962
Buku Teks