"Trends in lake water quality in southern Quebec following reductions in sulphur emissions," Environment Canada-Quebec Region, St. Lawrence Centre, Scientific and Technical Report ST-212E, 126 p. ###>"Trends in lake water quality in southern Quebec following reductions in sulphur emissions," Environnement Canada-Région du québec, Centre St-Laurent, Rapport scientifique et technique (Scientific and Technical Report) ST-212E, 126 p.