Active and Uncontrolled Asthma Among Children Exposed to Air Stack Emissions of Sulphur Dioxide from Petroleum Refineries in Montreal, Quebec: A Cross-Sectional Study oleh Leylâ Deger, Céline Plante, Louis Jacques, Sophie Goudreau, Stéphane Perron, John Hicks, Tom Kosatsky, Audrey Smargiassi