Galunska, B., B. Roussev, D. Gerova, and P. Kossev. “VITAMIN D: A POTENTIAL BIOMARKER FOR MORE AGGRESSIVE PROSTATE CANCER”. Biological Markers in Fundamental and Clinical Medicine (collection of abstracts) 2, no. 2 (November 15, 2018): 23-24. Accessed June 17, 2019. https://biologicalmarker.com/index.php/journal/article/view/94.