Pangestu, Y, S Setiati, Bambang Setiyohadi, and N Sukmana. 2018. “Prevalence and Factors Associated With Vitamin D Deficiency in Systemic Lupus Erythematosus Patients”. Indonesian Journal of Rheumatology 4 (1). https://doi.org/10.37275/ijr.v4i1.84.