Dynamic Skiametry and Methods of Testing, the Accommodation and Convergence of the Eyes: Being an Essay Contributed to the American, Encyclopedia of Ophthalmology. E-book. Formato PDF Charles Sheard   -  Forgotten Books, 2017  - 

The author presents to the reader the pages which follow in the hope that they may stimulate thought, suggest new methods and aid in the elucidation of some of the difficult problems of ocular refraction. Charles sheard. Department of Physiological Optics, Research Division, The American Optical Company, Southbridge, Mass, 1920.