by Dr. Nurdin Muhammad Suin $7.00
by Prof. Dr. Mahmud Syaltut $11.00
by Yayuk Sri Perwani, S.E $6.00
by Prof. Ir. Zoer'ani Djamal Irwan, M.Sc $9.00
by ISEI $18.00
by Mastenbroek, W.F.G. $7.00