Placebo-controlled trials on the safety and efficacy of tiotropium bromide in patients with chronic obstructive pulmonary disease and bronchitis. Int. J. Life. Sci. Biotech. Pharm. Sci. 2025;21(2):10-22. Accessed March 12, 2026. https://ijlbps.net/index.php/ijlbps/article/view/191