RT Journal Article SR Electronic T1 How well do we understand calcium and vitamin D? JF Cleveland Clinic Journal of Medicine JO Cleve Clin J Med FD Cleveland Clinic SP 505 OP 506 DO 10.3949/ccjm.85b.07018 VO 85 IS 7 A1 Brian F. Mandell YR 2018 UL http://www.ccjm.org/content/85/7/505.abstract AB