13.Lappe JM, Travers-Gustafson D, Davies KM et al. Vitamin D Supplementation reduces cancer risk: results of a randomized trial. Am J Clin Nutr 2007; 85:1586–1591. http://www.ncbi.nlm.nih.gov/pubmed/17556697
14.Carroll C, Cooper K, Papaioannou D, Hind D, Pilgrim H, Tappenden P. Supplemental calcium in the chemoprevention of colorectal cancer: a systematic review and meta-analysis. Clin Ther. 2010 May;32(5):789-803. http://www.ncbi.nlm.nih.gov/pubmed/20685491
15.Shaukat A, Scouras N, Schunemann H J. Role of supplemental calcium in the recurrence of colorectal adenomas: a metaanalysis of randomized controlled trials. American Journal of Gastroenterology 2005 Feb;100(2): 390-394. http://www.ncbi.nlm.nih.gov/pubmed/15667497