A nested case control study of plasma 25-hydroxyvitamin D concentrations and risk of colorectal cancer.
Wu K, Feskanich D, Fuchs CS, Willett WC, Hollis BW, Giovannucci EL.
J Natl Cancer Inst. 2007 Jul 18;99(14):1120-9. Epub 2007 Jul 10.
PMID: 17623801