Circulating 25-hydroxy-vitamin D and risk of cardiovascular disease: a meta-analysis of prospective studies - Wang, L; Song, Y; Manson, J E; Pilz, S; Marz, W; Michaelsson, K; Lundqvist, A; Jassal, S K; Barrett-Connor, E; Zhang, C; Eaton, C B; May, H T; Anderson, J L; Sesso, H D (Circ Cardiovasc Qual Outcomes, 2012)