Rüfer, Florian; Schröder, Anke; Erb, Carl (April 2005). "White-to-white corneal diameter: normal values in healthy humans obtained with the Orbscan II topography system". Cornea. 24 (3): 259–261. doi:10.1097/01.ico.0000148312.01805.53. ISSN0277-3740. PMID15778595.
Rüfer, Florian; Schröder, Anke; Erb, Carl (April 2005). "White-to-white corneal diameter: normal values in healthy humans obtained with the Orbscan II topography system". Cornea. 24 (3): 259–261. doi:10.1097/01.ico.0000148312.01805.53. ISSN0277-3740. PMID15778595.
Rüfer, Florian; Schröder, Anke; Erb, Carl (April 2005). "White-to-white corneal diameter: normal values in healthy humans obtained with the Orbscan II topography system". Cornea. 24 (3): 259–261. doi:10.1097/01.ico.0000148312.01805.53. ISSN0277-3740. PMID15778595.