Ahsan, Fikri Fathony. “The Effect of Numbered Heads Together (NHT) on Elementary School Students’ Mathematical Problem-Solving Ability in Geometry”. Mathline : Jurnal Matematika Dan Pendidikan Matematika, vol. 10, no. 3, Aug. 2025, pp. 659-70, doi:10.31943/mathline.v10i3.787.