Keirl, A., & Christie, C. (2007). Clinical optics and refraction: A guide for optometrists, contact lens opticians and dispensing opticians (1a. ed.). Elsevier.
Chicago-viite (17. p.)Keirl, Andrew, ja Caroline Christie. Clinical Optics and Refraction: A Guide for Optometrists, Contact Lens Opticians and Dispensing Opticians. 1a. ed. Edimburgo: Elsevier, 2007.
MLA-viite (9. p.)Keirl, Andrew, ja Caroline Christie. Clinical Optics and Refraction: A Guide for Optometrists, Contact Lens Opticians and Dispensing Opticians. 1a. ed. Elsevier, 2007.
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