tunik, tunik, Rahayu Niningasih, & Edi Yuswantoro. " The Effectiveness of Breath Relaxation with Balloon Blowing Technique towards Oxygen Saturation of COPD Patients." Jurnal Pendidikan Kesehatan (e-Journal) [Online], 9.2 (2020): 193-199. Web. 4 Sep. 2025