“Error Estimate and Superconvergence of a High-Accuracy Difference Scheme for Solving Parabolic Equations with an Integral Two-Space-Variables Condition”, Adv. Appl. Math. Mech., vol. 10, no. 2, pp. 362–389, Sept. 2018, doi: 10.4208/aamm.OA-2017-0067.