Eka Zhaki Safira Lubis, and Nelva Karmila Jusuf. 2020. “Risk Factors Analysis of Premature Canities in Medical Students of Universitas Sumatera Utara Class 2016-2018”. Sumatera Medical Journal 3 (1):48 - 58. https://doi.org/10.32734/sumej.v3i1.3543.