1. von Helmholtz, H. ,Physiologische Optik, 3rd ed., p. 152, Voss, Hamburg (1909).
2. Gullstrand, A. , appendix inPhysiologische Optik, 3rd ed., H. von Helmholtz , Ed., p. 299, Voss, Hamburg (1909).
3. Emsley, H. H. ,Visual Optics, 5th ed., Vol. 1, p. 360, Hatton Press Ltd., London (1952).
4. Le Grand, Y. ,Optique Physiologique I, p. 52, Ed. Rev. Opt., Paris (1953).
5. Theoretical Eye Model with Aspherics*