“Comparison Between Keros and Gera Classifications on Paranasal Sinuses Computed Tomography Scan in One Teaching Hospital in Medan, Indonesia”. Althea Medical Journal 12, no. 1 (March 30, 2025): 51–57. Accessed July 14, 2026. https://journal.fk.unpad.ac.id/index.php/amj/article/view/3659.