C. Izuchukwu, O. T. Mewomo, and C. C. Okeke, “Systems of variational inequalities and multiple-set split equality fixed-point problems for countable families of multivalued type-one mappings of the demicontractive type”, Ukr. Mat. Zhurn., vol. 71, no. 11, pp. 1480–1501, Feb. 2026, doi: 10.3842/umzh.v71i11.1530.