1. Vorzeigung ophthalmometrischer Instrumente;Donders;Zehender Mbl. Augenhk.,1863
2. Twenty-four hourly variations of the aqueous flow.;Ericson;Acta Ophth.,1958
3. Tonometer calibration.;Friedenwald;Am. J. Ophth.,1937
4. Friedenwald , J. S. Calibration of Tonometers Committee on Standardization of Tonometers of Am. Acad. Ophth., Decennial Report 1954
5. Der Rigiditäts-Koefficient (Friedenwald);Goldmann;Ophthalmologica,1957 a