00000nam 2200000zi 4500 9.939227 CaOODSP 20250422122830 m o d f cr |n||||||||| 240611t19871987onca o f000 0 eng d 0662154363 CaOODSP eng rda CaOODSP n-cn--- En57-24/15-1987E-PDF En57-24/15-1987E The ozone layer. Downsview, Ontario : Environment Canada, Atmospheric Environment Service, [1987] ©1987 1 online resource (6 pages) : illustrations text txt rdacontent computer c rdamedia online resource cr rdacarrier Fact sheet ; 15 Digitized edition from print [produced by Environment and Climate Change Canada]. Ozone layer depletion. Couche d'ozone Réduction. Canada. Atmospheric Environment Service, issuing body. PDF 3.40 MB https://publications.gc.ca/collections/collection_2025/eccc/en57/En57-24-15-1987-eng.pdf