Spectral analysis of linear differential operators and semigroups of difference operators
An extended version of this paper has appeared in [Differ. Equations 33, No. 10, 1305-1312 (1997); translation from Differ. Uravn. 33, No. 10, 1299-1306 (1997; Zbl 0929.34065)].
scientific article; zbMATH DE number 1050574