Ndaba, L W, et al. “Vitamin B12 Deficiency Presenting With Pulmonary Embolism: An Unusual Presentation”. African Journal of Thoracic and Critical Care Medicine, vol. 29, no. 3, Sept. 2023, pp. 139-40, https://doi.org/10.7196/AJTCCM.2023.v29i3.285.