Imani Filali, et al. “Association of Vitamin D Status With Recurrent Respiratory Tract Infections Among Children Attending a Tertiary Care Centre: A Cross-Sectional Study”. INTERNATIONAL JOURNAL OF CLINICAL, MEDICAL AND HEALTH SCIENCES, vol. 1, no. 3, Sept. 2025, pp. 38-45, https://ijcmhs.com/index.php/ijcmhs/article/view/47.