Rickard, J.A.
Barnes & Noble, 1952
Buku Teks
Hollister, C. Warren
John Wiley & Sons, 1968
Buku Teks
Scott, Jonathan F.
Appleton Century Croffs, 1933
Buku Teks
McGarry, Daniel D.
Littlefield, Adams, 1968
Buku Teks
Lyon, Bryce
Harper and Brothers, 1960
Buku Teks