Keumala, D. (2017) “ANALYSIS OF LIFESTYLE, KNOWLEDGE, ATTITUDE, AND KNOWLEDGE OF WOMEN AGED 20-50 YEARS OLD WITH VITAMIN D DEFICIENCY-INSUFFICIENCY IN NORTH SUMATERA, INDONESIA”, Sumatera Medical Journal, 1(01), pp. 1–7. doi: 10.32734/sumej.v1i01.75.