GromykA. P., Konet I. M., & Pylypiuk T. M. (2019). Hyperbolic boundary-value problem for a piecewisehomogeneous hollow cylinder. Ukrains’kyi Matematychnyi Zhurnal, 71(12), 1607-1617. Retrieved from http://umj.imath.kiev.ua/index.php/umj/article/view/714