1. Micromethod for phosphorus determination in research laboratories
2. N. R. Draper, and H. Smith (1966 ), Applied Regression Analysis , 1st ed. , pp.1 -35 , New York, J. Wiley & Sons.
3. S. J. Fomon (1974 ), Infant Nutrition , 2nd ed. , p.502 . Philadelphia, W. B. Saunders.