*A Critical Evaluation of the Historical Development of the Tactile Modes and Reading and an Analysis and Evaluation of Researches Carried out in Endeavors to make the Braille code Easier to Read and to Write*chapter 3: Early British Codeshttp://abstracts.iovs.org/cgi/content/abstract/46/5/4590
*:en:Tactile graphic*:en:Tangible symbol systems* A Critical Evaluation of the Historical Development of the Tactile Modes and Reading and an Analysis and Evaluation of Researches Carried out in Endeavors to make the Braille code Easier to Read and to Write* chapter 3: Early British Codes