Journée mondiale de l'ozone 2020-16 septembre
http://web.unep.org/ozonhttps://www.unenvironment.org/news-and-stories/video/unep-executive-director-message-world-ozone-day-2020action/international-day-preservation-ozone-layer-2018
http://web.unep.org/ozonhttps://www.unenvironment.org/news-and-stories/video/unep-executive-director-message-world-ozone-day-2020action/international-day-preservation-ozone-layer-2018