↑ Cross J, Broad MA, Harden B, Quint M, Ritson P, Thomas S. Respiratory physiotherapy: An on-call survival guide. Elsevier Health Sciences; 2008 Nov 25. ↑ Lewis LK, Williams MT, Olds TS. The active cycle of breathing technique: a systematic review and meta-analysis. Respiratory medicine. 2012 Feb 1;106(2):155-72.
https://www.physio-pedia.com/Active_Cycle_of_Breathing_Technique