Brinton, Crane, 1898-1968
The New American Library, 1958
Buku Teks
Sherry, John C.
Collier Books, 1963
Buku Teks
Chambers, Iain
Routledge, 2001
Buku Teks
Ople, Blas F.
The Institute for Public Policy, 2001
Buku Teks
Ayres, C.E.
Universty of Taxas Press , 1961
Buku Teks