1. A. V. Bitsadze, Certain Classes of Partial Differential Equations [in Russian], Nauka, Moscow (1981).
2. V. I. Korzyuk, “A fusion problem for equations of hyperbolic and parabolic types,” Differentsial'nye Uravneniya,4, No. 10, 1855–1866 (1968).
3. V. I. Korzyuk, “A mixed problem for certain nonstationary equations with discontinuous coefficients,” Differentsial'nye Uravneniya,6, No. 2, 343–357 (1970).
4. A. A. Samarskiî, The Theory of Difference Schemes [in Russian], Nauka, Moscow (1977).
5. A. A. Samarskiî and V. A. Gulin, “Criteria for stability of a family of difference schemes,” Dokl. Akad. Nauk,330, No. 6, 694–695 (1993).