Janson , Christer, and Gunnar Boman. “Intravenous Theophylline After Beta2-Agonist Treatment in Severe Acute Asthma. Effect on Patients Who Are Not Pre-Treated With Theophylline”. Upsala Journal of Medical Sciences 97, no. 2 (January 19, 2010). Accessed April 4, 2026. https://ujms.net/index.php/ujms/article/view/7530.