All links must be enclosed in the <noframes> section. A valid <noframes> section has at least one word of text or accessible html code. In addition, <noframes> should not be used to inform users that they must upgrade to a browser that supports frames. Testfile 6.5.1.4:<noframes> section invalid (link).
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" "http://www.w3.org/TR/REC-html40/loose.dtd"> <html lang="en"> <head> <title>aert1.0/6.5.1</title> </head> <frameset> <a href="mike.html">hello</a> <noframes> <p>content within noframes</p> </noframes> </frameset> <body> </body> </html>
W3C WAI: http://www.w3.org/WAI//
HTML Techniques for WAI 1.0: http://www.w3.org/TR/WCAG10-HTML-TECHS/