%0 Journal Article %A I. Jo %A N. Lažetić %T Estimate of the difference of derivatives of partial sums of decompositions corresponding to two arbitrary nonnegative selfadjoint extensions of two operators %J Differencialʹnye uravneniâ %D 1980 %P 598-619 %V 16 %N 4 %I mathdoc %U http://geodesic.mathdoc.fr/item/DE_1980_16_4_a2/ %G ru %F DE_1980_16_4_a2