Nababan, A.; Sari, A. N. P.; Manalu, G. J.; Lumban Gaol, N. T.; Hutagalung, T. I.; Waruwu, A. The Development of an Instructional Material Book for Increasing the Effectiveness of the Learning Process in the Department of Religious Extension Education. j. kependidikan. has. penelit. kaji. kepustakaan. bid. pendidik. pengajaran. n.a. 2023, 9, 924-935.