https://www.lexpera.com.tr/resmi-gazete/14-12-1998/23553 monthly 2026-10-09T14:54:39Z https://www.lexpera.com.tr/resmi-gazete/metin/manyezit-refrakter-sanayinde-kullanilan-ts-8542-standardinin-uygulanmasina-dair-teblig-mecburi-1 1998-12-14T00:00:00Z