Shopia University,
Majalah, Jurnal, Buletin
Departemen Luar Negeri AS / Biro Program Informasi Internasional,
Majalah, Jurnal, Buletin
Blazek, Ron, author
Libraries Unlimited, 2000
Buku Referensi
Lowrance, William W., author
Oxford University Press, 1985
Buku Teks
Blackwell Publishing, 2004
Buku Teks