\Bibitem{MakSal72} \by A.~M.~Makarov, V.~G.~Sal'nikov \paper Nonstationary shear flow of a viscoplastic medium \jour Prikl. Mekh. Tekh. Fiz. \yr 1972 \vol 13 \issue 4 \pages 133--137 \mathnet{http://mi.mathnet.ru/pmtf7502} \transl \jour J. Appl. Mech. Tech. Phys. \yr 1972 \vol 13 \issue 4 \pages 546--550 \crossref{https://doi.org/10.1007/BF00850401}