by Dr. Ibrahim Bafadal, M.Pd $7.00
by Norman Long $11.00
by Prof. Dr. S. Nasution, M.A. $6.00
by Prof. Dr. Sondang P. Siagian, M.P.A $7.00
by Chabib Thoha $6.00
by Drs. Agus Sujanto, dkk $9.00