Basic statistical methods, 2026-02-15T21:30:07+03:00 DEBUG: VuFind\ILS\Driver\Folio: Token taken from global cache: eyJhbGciOiJIUzI1NiJ9.eyJzdWIiO... - Downie, N. M. (Norville Morgan), 1910-; Heath, R. W. (Education for living series, 1959)