Artikel Jurnal
Machfud Sidik, author
Penerbit Universitas Indonesia, 2013
Buku Teks
George Philip Limited, 1999
Buku Referensi
Universiti Brunei Darussalam
Universiti Brunei Darussalam, 1997
Buku Referensi
Library Association Publishing, 1997
Buku Teks