Hoffman, Ross J.S., author
Littlefield, Adams, 1958
Buku Teks
Hollister, C. Warren, author
John Wiley & Sons, 1968
Buku Teks
McGarry, Daniel D., author
Littlefield, Adams, 1968
Buku Teks
Rickard, J.A., author
Barnes & Noble, 1952
Buku Teks
Scott, Jonathan F., author
Appleton Century Croffs, 1933
Buku Teks