by Nachrowi Djalal N $11.00
by Dr. B. Siswanto Sastrohadiwiryo $9.00
by Buckle, K.A., dkk $7.00
by Srivastava, A.C. $6.00
by Drs. O.P. Simorangkir $9.00
by Hermawan Kartajaya cs $12.00