Fihartini, S. A., and S. Muryaningsih. “Efforts to Enhance Students’ Communication Skills and Academic Achievement in Learning the Volume of Cube and Beam Spaces through the Problem-Based Learning (PBL) Model Assisted by Heyzine FlipbooksI in Five Grade of Danasri 01 Public Elementary School”. Proceeding Internasional Conference on Child Education, vol. 1, no. 1, July 2023, pp. 206-19, https://proceeding.unimar.ac.id/index.php/icce/article/view/24.