%0 Journal Article %A I. I. Shmulev %T Periodic solutions of boundary-value problems without initial conditions for quasi-linear parabolic equations %J Doklady Akademii Nauk %D 1961 %P 1318-1321 %V 139 %N 6 %I mathdoc %U http://geodesic.mathdoc.fr/item/DAN_1961_139_6_a11/ %G ru %F DAN_1961_139_6_a11