Darnley-Smith, Rachel, author
Sage Publications, 2003
Buku Teks
Kamien, Roger, author
McGraw-Hill, 1998
Buku Teks
Kamien, Roger, author
McGraw-Hill, 1998
Buku Referensi
McGraw-Hill Irwin, 2004
Multimedia
Westrup, J. A., author
William Collins Sons, 1959
Buku Referensi