Andrew Gnanaprakasam J, Veeramani G, and Manjanna K, “PROLONGED DURATION AND DOSE OF METFORMIN THERAPY AND ITS ASSOCIATED EFFECT OF VITAMIN B12 DEFICIENCY AMONG TYPE II DM PATIENTS: A CROSS SECTIONAL STUDY”., J Popl Ther Clin Pharmacol, vol. 30, no. 4, pp. 791–802, Apr. 2023, doi: 10.53555/jptcp.v30i4.2884.