Size of letters required for visibility as a function of viewing distance and observer visual acuity

Main Authors: Howett Gerald Leonard 1931-
Corporate Authors: United States. Occupational Safety and Health Administration; United States. National Bureau of Standards
Published: U.S. Dept. of Commerce, National Bureau of Standards For sale by the Supt. of Docs., U.S. G.P.O.,
Publication Dates: 1983.
Call Number: TS88/H859