Greenberg, Edward S.
Pearson/Longman, 2005
Buku Teks
Duncanson, Dennis J
Oxford University Press, 1968
Buku Teks
J.J. Raj
MPH Group, 2007
Buku Teks
Riant Nugroho Dwidjowijoto
Elex Media Komputindo, 2001
Buku Teks
Lowi, Theodore J.
Basic books, 1971
Buku Teks