Author,Title,Journal,ISSN,Publisher,Date,Volume,Number,Page,URL,URL(DOI) GOKE B,Efficacy and safety of vildagliptin monotherapy during 2-year treatment of drug-naive patients with type 2 diabetes : comparison with metformin,Horm Metab Res,,,2008,40,,892-895,https://cir.nii.ac.jp/crid/1570291225870073728,