An analysis of approaches to teaching the differential in elementary calculus 2026-02-16T08:08:12+03:00 DEBUG: VuFind\ILS\Driver\Folio: Token taken from global cache: eyJhbGciOiJIUzI1NiJ9.eyJzdWIiO... - Gwaiz, Saleh Abdulrahman (Indiana University, Faculty of the Graduate School, 1979)