Siagian HDR, Sirait M, Juliani R. PENGEMBANGAN ALAT PERAGA INDEKS BIAS DI SMA. JPF Unimed [Internet]. 2022 Jun. 29 [cited 2025 Jul. 2];11(1):6-10. Available from: https://jurnal.unimed.ac.id/2012/index.php/jpf/article/view/30346