Irfandita Khoirul Rosyidi et al. 2026. Development And Validation of the “Flipped Periodic Table”: Website-Based Chemistry Learning Media for Electron Configuration Material. EduMatSains : Jurnal Pendidikan, Matematika dan Sains. 10, 4 (Apr. 2026), 291–311. DOI:https://doi.org/10.33541/edumatsains.v10i4.7885.