Krishnan, G. D., M. H. Zakaria, and N. Yahaya. “Prevalence of Vitamin B12 Deficiency and Its Associated Factors Among Patients With Type 2 Diabetes Mellitus on Metformin from a District in Malaysia”. Journal of the ASEAN Federation of Endocrine Societies, vol. 35, no. 2, Aug. 2020, pp. 163-8, doi:10.15605/jafes.035.02.03.