%0 Journal Article %A N. I. Kipriyanova %T The mean-value formula for eigenfunctions of a singular second-order differential operator %J Differencialʹnye uravneniâ %D 1985 %P 1998-2001 %V 21 %N 11 %I mathdoc %U http://geodesic.mathdoc.fr/item/DE_1985_21_11_a20/ %G ru %F DE_1985_21_11_a20