Krishnan, Gayathri Divi, et al. “PREVALENCE OF VITAMIN B12 DEFICIENCY AND ITS ASSOCIATED FACTORS AMONG PATIENTS WITH TYPE 2 DIABETES ON METFORMIN IN MALAYSIA”. Journal of the ASEAN Federation of Endocrine Societies, vol. 34, no. 2, May 2022, p. 15, https://asean-endocrinejournal.org/index.php/JAFES/article/view/1867.