Cainzos-Achirica M, Bilal U, Kapoor K, Quispe Ayala R, McEvoy JW, Pladevall-Vila M, Blumenthal RS, Blaha MJ. Methodological issues in nutritional epidemiology research–sorting through the confusion. Current Cardiovascular Risk Reports. 2018 Feb;12:4. doi: 10.1007/s12170-018-0567-8
Fondell E, Balter O, Rothman KJ. Dietary intake and supplement use of vitamins C and E and upper respiratory tract infection. J Am Coll Nutr. 2011 Aug 1;30(4):248-58.