El-Shafie, K., N. Samir, R. Lakhtakia, R. Davidson, A. Al-Waili, M. Al-Mamary, and M. Al-Shafee. “Localised Skin Hyperpigmentation As a Presenting Symptom of Vitamin B12 Deficiency Complicating Chronic Atrophic Gastritis”. Sultan Qaboos University Medical Journal, vol. 15, no. 3, Aug. 2015, pp. 420-3, https://journals.squ.edu.om/index.php/squmj/article/view/2053.