Refraction status of youths, 12-17 years, United States /
Roberts, Jean,1918-
Slaby, David.
Rockville, Md., : National Center for Health Statistics;  [for sale by the Supt. of Docs., U.S. Govt. Print. Off.,  Washington],
1974.
Includes bibliographical references.
Visual acuity
Heterophoria
Ophthalmic lenses
Youth
Refraction, Ocular