\Bibitem{MarUrb88} \by A.~I.~Marchenko, V.~V.~Urban \paper Calculation of convergent shock waves \jour Prikl. Mekh. Tekh. Fiz. \yr 1988 \vol 29 \issue 2 \pages 84--89 \mathnet{http://mi.mathnet.ru/pmtf4765} \transl \jour J. Appl. Mech. Tech. Phys. \yr 1988 \vol 29 \issue 2 \pages 238--243 \crossref{https://doi.org/10.1007/BF00908588}