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NOTE (Revisions)

ONIX does not have a 1:1 mapping with EPUB or Schema.org accessibility metadata. Some accessibility assertions are made differently, and some may not currently be possible . This EPUB to ONIX crosswalk outlines the current high degree of overlap in metadata and will be updated as these two specifications evolve. It is important to note that ONIX 3.0 includes a number of new accessibility metadata codes. ONIX 2.1 can carry all the values from list 196 but has more limited accessibility metadata for other values and is not covered in this document. And not all may be carried in earlier versions of ONIX.