Smiddy WE, Hamburg TR, Kracher GP & Stark WJ : Keratoconus-contact lens or keratoplasty? Ophthalmology 95 : 487-492, 1998.
Koppen C, Kresps EO, Anthonissen L, Van Honey M et al : Scleral lenses reduce the need for corneal transplants in severe keratoconus. Am J Ophthalmol 185 : 43-47, 2018.
Eef van der Worp : A Guide to Scleral Lens Fitting College of Optometry, Pacific University, 2010. (https://www.fit-boston.eu/downloads/scleral_lenses/Scleral_Lens_Guide japanese.pdf)