1. Food sources and intakes of caffeine in the diets of persons in the United States;Frary;J Am Diet Assoc.,2005
2. 21 U.S.C. Sec. 321 2010 http://www.gpo.gov/fdsys/pkg/USCODE-2010-title21/html/USCODE-2010-title21-chap9-subchapII-sec321.htm
3. Report to Accompany H.R. 13254, Food Additives Amendment of 1958. H.R. No. 2284. 85 th Congress, 2 nd session 1958
4. Food and Drug Administration, US Department of Health and Human Services http://www.gpo.gov/fdsys/pkg/CFR-2012-title21-vol3/pdf/CFR-2012-title21-vol3-sec170-3.pdf 2012
5. Food and Drug Administration, US Department of Health and Human Services Food Additives. Proposed Definitions and Procedural and Intrepretative Regulations 1958