1. BRITISH STANDARD 3521 (1979). Glossary of Terms Relating to Ophthalmic Lenses and Spectacle Frames. Part 3: 'Glossary of terms relating to contact lenses. London: British Standards Institution
2. Treatise on Physiological Optics;SENFF,1846
3. ‘Corneal lenses with constant axial edge lift.’;STONE;Ophthal. Optician,1975
4. ‘Factors affecting peripheral curve design.’;BIBBY;Am. J. Optom.,1979
5. and ‘Factors affecting peripheral curve design. Part II: Specifying for reproducible performance.’ Am. J. Optom. 56, 10, 618–627