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2. W3C WAI. (2008). Web Content Accessibility Guidelines (WCAG) 2.0. Retrieved from https://www.w3.org/TR/WCAG20/
3. W3C WAI. (2010). Involving Users in Evaluating Web Accessibility. Retrieved from https://www.w3.org/WAI/eval/users.html
4. W3C WAI. (2013). Applying WCAG 2.0 to Non-Web Information and Communications Technologies (WCAG2ICT). WCAG2ICT Task Force. Retrieved from https://www.w3.org/WAI/GL/WCAG2ICT-TF/
5. W3C WAI. (2014). Overview: Web Site Accessibility Conformance Evaluation Methodology. https://www.w3.org/WAI/eval/conformance