TOMASZEK, Katarzyna, MUCHACKA-CYMERMAN, Agnieszka and ADAMCZYK, Marta. Believing in Yourself Matters! The Impact of Classroom Gratitude Week Intervention on Self-Regulation: The Role of Self-Esteem and Self-Effectiveness: An sich selbst zu glauben, ist wichtig! . Przegląd Badań Edukacyjnych (Educational Studies Review). Online. 19 May 2025. Vol. 2, no. 47, pp. 27-47. [Accessed 10 February 2026]. DOI 10.12775/PBE.2024.015.