“DEVELOPMENT OF POP-UP BOOK MEDIA FOR SPATIAL CONSTRUCTION MATERIALS FOR FOURTH GRADE STUDENTS AT STATE ELEMENTARY SCHOOL 121309 GURILLA PEMATANGSIANTAR”, Jurnal Merah Putih Sekolah Dasar, The Indonesian Journal of Primary School Education, vol. 1, no. 1, pp. 18–26, Jan. 2024, doi: 10.24114/jmpsd.v1i1.56072.