Simbolon, K., Ditasona, C. and Setiawan, L.F. 2025. Improving Mathematical Understanding on Geometry for 9th Grade Students through Three-Dimensional Mathematics Learning Media Based on Virtual Reality. Brillo Journal. 4, 1 (Mar. 2025), 59–75. DOI:https://doi.org/10.56773/bj.v4i1.71.