Bibpurl.oclc.org links are surfaced by the Links from WorldCat record 856 and 956 to open access content / free content and the Links from DOI settings found in the Service Configuration under WorldCat Discovery and WorldCat Local > Full Text and Open Access Links > WorldCat Local Search Results // WorldCat Discovery Search Results and Detailed Views. You may need to deselect both of these settings to stop bibpurl.oclc.org links from surfacing on your Discovery records. If you do choose to surface these links and are seeing links that don't resolve to the resource, you can report broken links to OCLC.