1) G. D. Pettit and W. J. Turner. Refractive index of InP, J. Appl. Phys. 36, 2081 (1965)
2) A. N. Pikhtin and A. D. Yas’kov. Disperson of the refractive index of semiconductors with diamond and zinc-blende structures, Sov. Phys. Semicond. 12, 622-626 (1978) (as cited in Handbook of Optics, 2nd edition, Vol. 2. McGraw-Hill 1994)
3) Handbook of Optics, 2nd edition, Vol. 2. McGraw-Hill 1994
* Ref. 3 provides a Sellmeier equation based on the data from Ref. 1 and Ref. 2.