Lamb, Charles W., author
Houghton Mifflin, 1987
Buku Teks
Lamont, Douglas, author
Blackwell Publishers, 1996
Buku Referensi
Elex Media Komputindo, 1994
Buku Teks
Kurtz, David L., author
The Dryden Press , 1981
Buku Teks
Alex Soemadji Nitisemito, author
Ghalia Indonesia, 1984
Buku Teks