T. H. H. Dang and B. Nguen, “Tikhonov regularization method for a system of equilibrium problems in Banach spaces”, Ukr. Mat. Zhurn., vol. 61, no. 8, pp. 1098–1105, Aug. 2009, Accessed: Dec. 06, 2025. [Online]. Available: https://umj.imath.kiev.ua/index.php/umj/article/view/3083