References

http://www.jsei.org/patient_care/home_eyeworks.htm

http://www.eyecare2020.com/faqs

http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0002018/

http://EzineArticles.com/266267

http://www.laser-eye-surgery-review.com/refractive-errors.html

http://www.nnjei.com/fact-sheet-presbyopia

http://www.presbyopia-contacts.com/contact-lens-history.html

http://www.askfactmaster.com/Lens_%28optics%29

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Malcara, Daniel. Handbook of optical design[ electronic resource] 1937. New York : Marcel 1994.

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