%0 Journal Article %A Yu. G. Abakumov %A V. E. Banine %T On some classes of operators, including the class of positive operators %J Izvestiâ vysših učebnyh zavedenij. Matematika %D 1996 %P 3-5 %N 8 %I mathdoc %U http://geodesic.mathdoc.fr/item/IVM_1996_8_a0/ %G ru %F IVM_1996_8_a0