"2006-04-25" . _:vb50819503 . _:vb50819505 "Wendy Chisholm" . . _:vb50819504 "John Slatin" . _:vb50819504 . _:vb50819505 . _:vb50819506 . _:vb50819505 . . _:vb50819504 . "Requirements for WCAG 2.0" . . _:vb50819503 "Gregg Vanderheiden" . _:vb50819506 . _:vb50819503 . . _:vb50819506 .