1. A description of the reflecting phorometer and a discussion of the possibilities concerning torsion of the eyes Author(s): Verhoeff, F. H. (Frederick Herman), 1874-1968, author Publication: [New York?] : [publisher not identified], [1899] Subject(s): Optical DevicesEquipment DesignOptometry -- instrumentationOcular Motility Disorders -- diagnosisTorsion Abnormality -- diagnosis
2. Two new astigmatic charts Author(s): Verhoeff, F. H. (Frederick Herman), 1874-1968, author Publication: Chicago : Ophthalmic record, 1899 Subject(s): Astigmatism -- diagnosisVision Tests -- instrumentation