Greenstein, Ben, author
Balckwell Publishing, 1994
Buku Teks
Martin, Constance R.
Oxford University Press, 1985
Buku Teks
Hadley, Mac E.
Prentice-Hall, 2007
Buku Teks
editor, J. Larry Jameson
McGraw-Hill, 2017
Buku Teks
Turner, C. Donnell, author
Airlangga University Press, 1988
Buku Teks