Eskridge, J B An investigation of voluntary vergence. [electronic resource] - American journal of optometry and archives of American Academy of Optometry Sep 1971 - 741-6 p. digital Publication Type: Journal Article ISSN: 0002-9408 Standard No.: 10.1097/00006324-197109000-00005 doi Subjects--Topical Terms: Accommodation, OcularEye MovementsHumansOculomotor Muscles--physiology