Triwoelandari, R., and A. Fadilah. “PENGARUH MODEL PEMBELAJARAN KOOPERATIF TIPE NUMBERED HEADS TOGETHER (NHT) TERHADAP TANGGUNG JAWAB DAN KERJA KERAS SISWA”. Attadib Journal of Elementary Education, vol. 1, no. 1, Jan. 2015, pp. 33-50, https://ejournal.uika-bogor.ac.id/index.php/at-tadib/article/view/132.