1. Churton T: Multiple aneurysms of the pulmonary artery. Br Med J. 1897, 1: 1223-1225.
2. Global Initiative for Asthma (GINA), National Heart, Lung and Blood Institute (NHLBI): Global strategy for asthma management and prevention. 2006, Bethesda (MD): Global Initiative for Asthma (GINA), National Heart, Lung and Blood Institute (NHLBI), 339-Available from:
http://www.ginasthma.com
3. Risenga SM: Difficult-to-control asthma in children – an overview. Curr Allergy Clin Immunol. 2011, 24: 18-21.
4. Weiss P, Rundell KW: Imitators of exercise-induced bronchoconstriction. Allergy Asthma Clin Immunol. 2009, 5: 7-10.1186/1710-1492-5-7.
5. American Thoracic Society: Current understanding, recommendations, and unanswered questions. In Proceedings of the ATS workshop on refractory asthma. Am J Respir Crit Care Med. 2000, 162: 2341-2351.