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. 1984 Nov;102(11):1712.
doi: 10.1001/archopht.1984.01040031396035.

A mechanical three-step test

E M Perlman

A mechanical three-step test

E M Perlman. Arch Ophthalmol. 1984 Nov.

Abstract

A simple mechanical binary search device is described that can be used to perform the Parks' three-step test. Instructions to make the device from light cardboard are provided.

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