Artikel Jurnal
Sexton, John, author
M. Evans and Company, 1986
Buku Teks
Proximore, Senator William, author
Henry Regnery, 1964
Buku Teks
Hollis, Christopher, author
Hollis & Carter, 1949
Buku Teks
Albright, Madeleine, author
Harper Perenial, 2008
Buku Teks