Chest and pulmonary conditions:  Pediatric Practice: Sports Medicine/ 
Patel D.R., & Greydanus D.E., & Baker R.J.(Eds.),  
 - NewYork:  McGraw-Hill,  c2009 . 
 - Online resource 
<br/><br/> https://accessphysiotherapy.mhmedical.com/content.aspx?bookid=450&sectionid=40190607