POTAPENKO, S. V. Determination of significant prognostic factors in the development of magnesium deficiency in children and adolescents with gastroesophageal reflux disease. Journal of Education, Health and Sport. Online. 14 December 2020. Vol. 10, no. 12, pp. 125-137. [Accessed 16 January 2026]. DOI 10.12775/JEHS.2020.10.12.012.