1. R. C. McNamara et alia, “Materials for Large Space Optics, Phase I Final Technical Report,” AFML-TR-78–12 (1978)
2. S. R. Skaggs, “Zero and Low Coefficient of Thermal Expansion Polycrystalline Oxides,” Los Alamos Report No. LA-UR77–1307 and presented at. Int. Colloquium on Refractory Oxides, Odeillo, France (1977)
3. Y. S. Touloukian, R. K. Kirby, R. E. Taylor and T. Y. R. Lee, Thermophysical Properties of Matter-TPRC Data Series, Volumes 12 and13, (Thermal Expansion-Metallic Elements and Alloys, and Non metallic Solids /IFI/Plenum Press (1977)
4. W. R. Manning, O. Hunter, F. W. Calderwood and D. W. Stacy, “Thermal Expansion of Nb2O5. ” J. Am. Ceram. Soc. 55, pp. 342–347 (1972)
5. L. G. Van Uitert et alia, “Physical Properties of Thorium Fluoride,” Met. Res. Bull, Vol. 11, pp 669–672 (1976)