\Bibitem{Khl84} \by A.~M.~Khludnev \paper Existence of solutions in ideal Hencke plasticity \jour Prikl. Mekh. Tekh. Fiz. \yr 1984 \vol 25 \issue 1 \pages 174--177 \mathnet{http://mi.mathnet.ru/pmtf5450} \transl \jour J. Appl. Mech. Tech. Phys. \yr 1984 \vol 25 \issue 1 \pages 160--163 \crossref{https://doi.org/10.1007/BF00916887}