This information is available online and the ICAM staff talks about these issues often. There is always confusion, understandably, so let’s give it another run through.
  1. NIMAC - National Instructional Materials Accessibility Center:
  1.  APH - American Printing House for the Blind:
  1.  MAMP - Miami Accessible Media Project:
  1. Learning Ally:
  1.  Bookshare:
Further considerations:
Thanks so much!