%0 Journal Article %A S. Z. Levendorskii %T Asymptotic behavior of the spectrum of problems of the form $Au=tBu$ for operators that are elliptic in the Douglis--Nirenberg sense %J Funkcionalʹnyj analiz i ego priloženiâ %D 1984 %P 84-85 %V 18 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/item/FAA_1984_18_3_a15/ %G ru %F FAA_1984_18_3_a15