Etter, Carl
Wilcox & Follett, 1949
Buku Teks
Richardson, Bradley M.
Harper Collins, 1984
Buku Teks
Scalapino, Robert A.
University of California Press, 1967
Buku Teks
Shillony, Ben-Ami
Clarendon Press, 1991
Buku Teks
Quigley, Harold S.
University of Minnesota Press, 1956
Buku Teks