Minal Aidin A. Rahiem, author
Fakultas Ilmu Pengetahuan dan Budaya Universitas Indonesia, 1981
UI - Skripsi (Membership)
Beer, Nick
Butterworth-Heinemann , 1994
Buku Teks
Carrison, Dan, author
[American Management Association, ], 1999
eBooks
Mustafa, Shakir, author
Jami`at al-Duwal al-Arabiyat, 1958
Buku Teks
Khayat, Muhammad Abu`lfutuh, author
Maktabat al-Ma`rifah, 1937
Buku Teks