1. AOAC., 1970 . "Official Methods of Analysis ," 11th ed. , p. 777 . Association of Official Analytical Chemists, Washington, D. C.
2. Association of Vitamin Chemists . 1966 . "Methods of Vitamin Assay ," 3rd ed. , p. 287 . Wiley and Sons, New York, N. Y.
3. Automated determination of vitamin C in some fortified foodstuffs
4. ? Freed, 1966 .