3 1 50 suatu pengantar Heny Triastuti Kurnianingsih Additional Author Eka Nurmala Sari Primary Author Yuswar Effendy Additional Author mixed material 9786026970589 Medan Perdana Publishing 2015 suatu pengantar Heny Triastuti Kurnianingsih Additional Author Eka Nurmala Sari Primary Author Yuswar Effendy Additional Author mixed material 9786026970589 Medan perdana pubising 2015 perusahaan dagang dan manufaktur Fitriani Saragih Primary Author Ikhsan Abdillah Additional Author Zulia Hanum Additional Author Heny Triastuti Kurnianingsih Additional Author mixed material 9786028826785 Medan Perdana Publishing 2014 30184822_10212239799169894_330378437_n.jpg.jpg