RT Journal Article SR Electronic T1 Evidences for a protective role of vitamin D in COVID-19 JF RMD Open JO RMD Open FD EULAR SP e001454 DO 10.1136/rmdopen-2020-001454 VO 6 IS 3 A1 Maurizio Cutolo A1 Sabrina Paolino A1 Vanessa Smith YR 2020 UL http://rmdopen.bmj.com/content/6/3/e001454.abstract AB