by Prof. Dr. Sondang P. Siagian, M.P.A
$9.00

by Yernelis Sukma, M.S., & Yakup
$7.00

by Ir. Eddy Afrianto & Ir. Evi Liviawaty
$6.00

by Stephens Speight
$5.00

by Mike Freedman
$11.00

by Susilowati
$13.00