%0 Journal Article %A V. V. Kartak %T Extensions of point-invariant classes of third-order ordinary-differential equations %J Izvestiâ vysših učebnyh zavedenij. Matematika %D 2006 %P 29-32 %N 10 %I mathdoc %U http://geodesic.mathdoc.fr/item/IVM_2006_10_a3/ %G ru %F IVM_2006_10_a3