by Ir. Budi Samadi & Ir. Bambang Cahyono $7.00
by Ir. H. Rahmat Rukmana $5.00
by Drs. Wishnubroto Widarso $5.00
by $4.00
by Dr. M. Umer Chapra $12.00
by Imam Ibnul Qayyim $6.00