Comparing Frei-Chen & Sobel Edge Detector in Face Emotion Recognition with Euclidean Distance and LVQ Network. International Journal of Advanced Research in Computer Science, [S. l.], v. 3, n. 5, p. 67–71, 2017. DOI: 10.26483/ijarcs.v3i5.1358. Disponível em: https://www.ijarcs.info/index.php/Ijarcs/article/view/1358. Acesso em: 22 feb. 2026.