Mr. Vinayak Kurale, Dr. Archana D. Methe, Miss. Smruti Umesh Kurulkar, Dr. Gloria Naik. TO COMPARE THE EFFICACY OF BUTEYKO BREATHING EXERCISE AND 90/90 BALL & BALLON BREATHING EXERCISE IN PATIENTS WITH STAGE 1 AND STAGE 2 CHRONIC OBSTRUCTIVE PULMONARY DISEASE. J Popl Ther Clin Pharmacol [Internet]. 2026 Jan. 21 [cited 2026 Sep. 30];33(1):558-6. Available from: https://www.jptcp.com/index.php/jptcp/article/view/12796