Some links from PDF-23 technique result in 404

Hi everyone,

Apologies if this is not the right place to post.

In the 1st paragraph of description of PDF-23 
<https://www.w3.org/WAI/WCAG21/Techniques/pdf/PDF23> technique there are 
2 links, and both of them are not working. If someone could fix the 
links, that would be great!

Thanks!


-- 
Best,
Vlad