"The Montreal Protocol that went into force in 1989 and which was hailed by Kofi Annan as ""... the single most successful international agreement to date ..."" was aimed at protecting what?"
Ozone layer Stratospheric ozone Ozone Layer Ozonosphere The ozone layer Stratosphere ozone Ozone shield Stratospheric Ozone
stratosphere ozone stratospheric ozone ozonosphere ozone shield ozone layer
ozone layer
WikipediaEntity
Ozone layer