W3C Working Group - Keyboard Accessible Understanding Guideline 2.1
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)
...
List of John Gill publications for accessible keypads and user interfaces
US Dept of Education - Rehabilitation Engineering Research Centers
W3C Working Group - Keyboard Accessible Understanding Guideline 2.1
Section 508 Blog How to Tell if a Keyboard is Accessible
...