by Drs. Muchdarsyah Sinungan $9.00
by Prof. Dr. Sondang P. Siagian, M.P.A $7.00
by Ny. Susmayati, B.A dan Ny. Hj. Asnidar $7.00
by Drs. Amin Wijaja Tunggal, M.B.A $6.00
by Dra. Dwi Hayu Agustini, MBA $9.00
by Muzaham, Fauzi $7.00