Kalenderwoche in Datum in ORACLE

SELECT
TRUNC(TO_DATE('2511[Jahr]', 'DDMMYYYY'), 'IYYY') + ([KW] - 1) * 7 AS date_from,
TRUNC(TO_DATE('2511[Jahr]', 'DDMMYYYY'), 'IYYY') + ([KW] - 1) * 7 + 6 AS date_to
FROM sys.dual;