Franklin, John Hope, author
Alfred A.Knopf, 1961
Buku Teks
Moonitz, Maurice
New York, N.Y. Garland Publishing 1990,
Buku Teks
Taylor, Overton H.
Kogakusha Company,Ltd., 1960
Buku Teks
Gettell, Raymond G.
Appleton-Century-Crofts, 1928
Buku Teks
Canning, Joseph
Routledge, 1996
Buku Teks