1. The System SiO2-P2O5
2. 2J. A. Audley , Silica and Silicates , pp.9 -10 ; BailliPre Tindall & Cox, Ltd., London, 1921 . 9 pp.
3. 5W. R. Jacoby , "Equilibrium Relations in a Portion of the System SiO2-P2O6," University Microfilms (Ann Arbor, Mich.), Publ. No. 22528, 119 pp.Dissertation Abstr., 17 , 119 (1957 ).