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Documentation from the W3C on creating accessible PDFs. The World Wide Web Consortium (W3C) notes: “Publication of techniques for a specific technology does not imply that the technology can be used in all situations to create content that meets WCAG 2.0 success criteria and conformance requirements. Developers need to be aware of the limitations of specific technologies and provide content in a way that is accessible to people with disabilities.”
PDF Techniques | Techniques for WCAG 2.0 (w3.org)
Create and verify PDF accessibility, Acrobat Pro
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Creating accessible PDF documents | Foxit
Designing for colourblind users
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