”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), s. 53–57. Saatavissa: https://www.ojshostng.com/index.php/ajbr/article/view/1689 (Viitattu: 5 huhtikuuta 2026).