Arican S, Hacibeyoglu G, Cicekci F, Topbal I, Sinan Iyisoy M. Is vitamin D deficiency associated with mortality in intensive care patients? an observational retrospective study . Ann Med Res . 2021;25(3):0380-0385. Accessed September 16, 2026. http://www.annalsmedres.org/index.php/aomr/article/view/1469