Sudarsono, S.; Baeti, N.; Sartika, D. Reconstructing Geometric Concepts through Uma Lengge: An Ethnomathematics-Based Design Study to Enhance Students’ Contextual Problem-Solving Skills. form.j.jipm 2026, 16 (2), 319-334. https://doi.org/10.30998/formatif.v16i2.3425.