1. Applanation tonometry and central corneal thickness;Ehlers;Acta Ophthalmol,1975
2. Sources of error with use of Goldmann-type tonometers;Whitacre;Surv Ophthalmol,1993
3. Measurement of intraocular pressure: A study of its reproducibility;Phelps;Graefes Arch Clin Exp Ophthalmol,1976
4. Sources of variability in the results of applanation tonometry;Motolko;Can J Ophthalmol,1982
5. Becker-Shaffer's Diagnosis and Therapy of the Glaucomas;Hoskins,1989