«Prevalence of Vitamin D Deficiency and Insufficiency Across Trimesters of Pregnancy in Maiduguri, Nigeria: A Cross-Sectional Study» (2021) African Journal of Biomedical Research, 24(1), сс. 53–57. доступно на: https://ojshostng.com/index.php/ajbr/article/view/1689 (просмотрено: 5 апрель 2026).