by Abuddin Nata $7.00
by Prof. Dr. Sondang P. Siagian, M.P.A $9.00
by Prof. Dr. Oemar Hamalik $9.00
by Prof. Dr. Husaini Usman, M.Pd dan R. Purnomo Setiady Akbar, S.Pd., M.Pd $6.00
by Drs. Basir Barthos $11.00
by Prof. Dr. Sudarwan Danim $11.00