Sibomana, A., C. B. Nicol, W. Nzabalirwa, F. Nsanganwimana, C. Karegeya, and J. Sentongo. “Factors Affecting the Achievement of Twelve-Year Basic Students in Mathematics and Science in Rwanda”. International Journal of Learning, Teaching and Educational Research, vol. 20, no. 7, July 2021, pp. 61-84, https://ijlter.myres.net/index.php/ijlter/article/view/59.