Digital signal processing 2026-02-15T19:10:44+03:00 DEBUG: VuFind\ILS\Driver\Folio: Token taken from global cache: eyJhbGciOiJIUzI1NiJ9.eyJzdWIiO... - Oppenheim, Alan V., 1937-; Schafer, Ronald W., 1938- (Prentice-Hall, 1975)