“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), pp. 53–57. Available at: https://www.ojshostng.com/index.php/ajbr/article/view/1689 (Accessed: 6 April 2026).