W3C Working Group - Keyboard Accessible Understanding Guideline 2.1
Wisco Systems Telephone Accessibility
List of John Gill publications for accessible keypads and user interfaces
US Dept of Education - Rehabilitation Engineering Research Centers
Just Ask: Integrating Accessibilty Throughout Design (online book)
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List of John Gill publications for accessible keypads and user interfaces
US Dept of Education - Rehabilitation Engineering Research Centers
Section 508 Blog How to Tell if a Keyboard is Accessible
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