Co-Authors Damanik, Elfina O P Damanik, Yesni Riana Girsang, Rosita Manawari Girsang, Yuli S N Haloho , Dasmaika Apriani Khairun Annisa Mahaitin H Sinaga Pandapotan Simatupang Perangin - angin, Dermawan Purba, Desmi Triyanti Purba, Fariaman PURBA, JOHANES WILFRID PANGIHUTAN Resna Napitu Roslina Tamara Saragih, Esteriani Saragih, Liharman Saragih, Yoan Hendrawan Junpridan SIMBOLON, PIRMA