1. Bodansky, M.:“Introduction to Physiological Chemistry.” John Wiley and Sons, Inc., New York, 1938 (4th Edition).
2. Cantarow, A. and Trumper, M.: “Clinical Biochemistry.” W. B. Saunders Co., Philadelphia, 1939 (2nd Edition).
3. Clark, W. M.: “The Determination of Hydrogen Ions.” The Williams and Wilkins Co., Baltimore, 1928 (3rd Edition).
4. Collins, D. C.: A More Accurate Indicator in Determining the Total Acidity in Quantitative Gastric Analyses0.Med. Rec., 144:183, 1936.
5. Gradwohl, R. B. H.: “Clinical Laboratory Methods and Diagnosis.” C. V. Mosby Co., St. Louis, 1938 (2nd Edition).