RT Journal Article SR Electronic T1 Fish Oil versus Cod Liver Oil: Is Vitamin D a Reason to Go Back to the Future JF The Journal of the American Board of Family Practice JO J Am Board Fam Med FD American Board of Family Medicine SP 445 OP 446 DO 10.3122/jabfm.18.5.445-b VO 18 IS 5 A1 Celia M. Ross YR 2005 UL http://www.jabfm.org/content/18/5/445.1.abstract AB