1. L. A. Zolina, “On a boundary value problem for a model equation of hyperbolo-parabolic type,” USSR Comput. Math. Math. Phys. 6 (6), 63–78 (1966). https://doi.org/10.1016/0041-5553(66)90162-5
2. H. G. Bzkikhatlov and A. M. Nakhushev, “A boundary value problem for a mixed equation of parabolic-hyperbolic type,” Sov. Math., Dokl. 9, 1349–1352 (1968).
3. T. D. Dzhuraev, Boundary Value Problems for Equations of Mixed and Mixed-Composite Types (Izd-vo Fan, Tashkent, 1979).
4. T. D. Dzhuraev, A. Sopuev, and A. Mamazhanov, Boundary Value Problems for Parabolic-Hyperbolic Equations (Izd-vo Fan, Tashkent, 1986).
5. K. B. Sabitov, “On the theory of equations of mixed parabolic-hyperbolic type with a spectral parameter,” Differ. Equations 25 (1), 93–100 (1989).