Najah Rajab Ghoumah and Mustafa Saieh 2026. Association Between Serum Vitamin D Levels and Acute Respiratory Tract Infections Among Preschool Children in Gharyan Hospital, Libya. African Journal of Advanced Pure and Applied Sciences . 5, 2 (Jun. 2026), 313–322. DOI:https://doi.org/10.65418/ajapas.v5i2.2031.