Pérez-García, Ana María, José Bermúdez, Pilar Sanjuán, Beatriz Rueda, and Ángeles Sánchez-Elvira-Paniagua. “Perceived Competence and Level of Task Difficulty: Performance and Heart Rate Reactivity”. Acción Psicológica 1, no. 1 (July 9, 2012): 31–44. Accessed May 29, 2023. https://revistas.uned.es/index.php/accionpsicologica/article/view/540.