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2. EU SCIENTIFIC COMMITTEE ON FOOD, Opinion On A Request For The Use Of Algal Beta-Carotene As A Food Colour (expressed on 13th June 1997).
3. EUROPEAN COMMISSION HEALTH & CONSUMER PROTECTION DIRECTORATE-GENERAL, Opinion of the Scientific Committee on Food on β-carotene from Blakeslea trispora (adopted on 22 June 2000, and corrected on 7 September 2000).
4. OFFICIAL JOURNAL OF THE EUROPEAN COMMUNITIES, European Parliament and Council Directive 94/36/EC of 30 June 1994 on colours for use in foodstuffs.
5. CODE OF FEDERAL REGULATIONS - TITLE 21, Part 73 Listing of Color Additives Exempt from Certification, U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, Office of Cosmetics and Colors.