Kotwal, O. P.
McGraw-Hill, 1987
Buku Teks
Voorhoeve, Petrus
Martinus Nijhoff, 1955
Buku Teks
Burton, Graeme
McGraw-Hill, 2010
Buku Teks
edited by Larry Earl Bone
Champaign, Illinois University of Illinois Graduate School of Library Science 1968, 1968
Buku Teks
Quigley, Harold S.
World Peace Foundation, 1938
Buku Teks