Sumantri, Stevent, Siti Setiati, Dyah Purnamasari, and Esthika Dewiasty. 2016. “Relationship Between Metformin and Frailty Syndrome in Elderly People With Type 2 Diabetes”. Acta Medica Indonesiana 46 (3). http://actamedindones.org/index.php/ijim/article/view/87.