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How Visual Acuity is Measured

Visual Acuity Measurement Standard, International Council of Ophthalmology, 1984

Visual Acuity of the Human Eye

Golovin-Sivtsev Table for testing visual acuity - used in the USSR and post-Soviet states in different formats (as pdf or cdr files)

Visual Acuity  Chapter from the Webvision reference, University of Utah