ReportMonitoring of the Ozonlayer. Annual Report 1991. Dahlback, A.; Braathen, G O.; Kåstad, B A.; Stordal, F.Publication details Series: NILU OR 52/92 Publisher: NILU Year: 1992 ISBN: 82-425-0391-5 File: NILU OR 52/92 (pdf)