by Mastenbroek, W.F.G. $7.00
by Prof. Dr. Sondang P. Siagian, M.P.A $9.00
by Michael J. Tang $13.00
by Drs. Hg. Suseno Triyanto Widodo $6.00
by Titie Said $6.00
by Tuti Heraty Noerhadi $9.00