P. . Choirina, I. M. . Fitriani, U. D. . Rosiani, M. N. . Mufti, F. A. . Arsistawa, and P. P. . Darajat, “Improved Micro-expression Recognition: An Apex Frame-Based Approach Feature Tracking and KLT”, J. Tek. Inform. (JUTIF), vol. 6, no. 2, pp. 593–608, Apr. 2025.