Sultana, Naznin, et al. “Vitamin D3 Supplementation on Lung Functions and Exercise Tolerance in D3 Deficient Asthma COPD Overlap Syndrome Patients - A Randomized Controlled Trial”. Journal of Bangladesh Society of Physiologist, vol. 17, no. 1, Dec. 2022, pp. 21-33, doi:10.3329/jbsp.v17i1.63213.