by Dr. Hamzah B. Uno, M.Pd
$9.00

by Ir. Juhaeni Radi
$0.00

by Prof. Dr. Sondang P. Siagian, M.P.A
$11.00

by Drs. Firman B. Aji dan Drs. Martin Sirait
$9.00

by Ir. Hatta Sunanta, B.Sc., MS
$6.00

by Prof. Syekh Abdul Aziz Syawisy
$6.00