Yang, X. Y., and K. Wang. “Spatial Transformer Networks for Facial Action Unit Detection: Modeling Inter-AU Dependencies via Structured Attention”. Advanced Electromagnetics 15, no. 3 (August 21, 2026): 9761–9771. Accessed August 26, 2026. https://www.aemjournal.org/index.php/AEM/article/view/4169.