Urwyler, Pascal, Nebal Abu Hussein, Pierre O. Bridevaux, Prashant N. Chhajed, Thomas Geiser, Peter Grendelmeier, Ladina Joos Zellweger, et al. “Predictive Factors for Exacerbation and Reexacerbation in Chronic Obstructive Pulmonary Disease: An Extension of the Cox Model to Analyze Data from the Swiss COPD Cohort”. Multidisciplinary Respiratory Medicine 14, no. 1 (February 5, 2019). Accessed July 7, 2024. https://mrmjournal.org/index.php/mrm/article/view/6.