Lippi, Giuseppe, Antonio Nouvenne, Andrea Ticinesi, Patrizia Bonelli, Gian Luca Salvagno, Gianfranco Cervellin, and Gian Cesare Guidi. “The Burden of Vitamin D Deficiency in a Mediterranean Country Without a Policy of Food Fortification”. Acta Biomedica Atenei Parmensis 86, no. 1 (April 27, 2015): 59–62. Accessed October 26, 2021. https://www.mattioli1885journals.com/index.php/actabiomedica/article/view/4243.