by Prof. Dr. Komarudin Hidayat $5.00
by Dellmann, H. Dieter $7.00
by Dr. Ir. Muhammad Rasyaf, MS $7.00
by Bambang Agus Murtidjo $6.00
by Drs. Radno Harsanto, M.Si $9.00
by A. Widyamartaya, B.A $4.00