Ayvazyan, G., Baghdasaryan, N., Avetisyan, L., Mnatsakanyan, N., & Aleksanyan, L. (2023). Serum vitamin D concentration in children with pneumonia and acute respiratory infections, risk factors for its low level. The Journal of Infection in Developing Countries, 17(10), 1413–1419. https://doi.org/10.3855/jidc.17749