by Ir. Abbas Siregar Djarijah
$6.00

by Prof. Dr. S. Nasution, M.A.
$7.00

by H. Rahmat Rukmana
$5.00

by Dede Juanda J.S. & Ir. Bambang Cahyono
$6.00

by Drs. Ec. Alex. S. Nitisemito dan Drs. M. Umar Burham. M.S
$6.00

by Suhardi, dkk
$11.00