Larra JD, Barrera DM, Bayadas LJ, Ellipse CA, Lumanas RD, Valdez JRR, et al. Evaluation of Project GTR (Gravitational Teaching Resource) as an Instructional Material for the General Theory of Relativity. J Res Educ Pedagog [Internet]. 2026 Aug. 3 [cited 2026 Aug. 7];3(3):396–410. Available from: https://spm-online.com/jrep/index.php/journal/article/view/187