The links you are seeing are populated by Open Access 856 links that are included in the MARC record. You may also see some linked OCLC numbers with the same display.
Any library with a cataloging subscription can review and edit the 856 links within Connexion or WorldShare Record Manager.
The cataloging subscriber can delete any of those URLs if they find its pointing to the incorrect resource or is no longer valid.
If you would like OCLC to review the links, please email bibchange@oclc.org.