Rasulov, M. S., and Zh. O. Takhirov. 2017. “Problem With Free Boundary for the Systems of equations of Reaction-Diffusion Type”. Ukrains’kyi Matematychnyi Zhurnal 69 (12), 1690-1700. https://umj.imath.kiev.ua/index.php/umj/article/view/1812.