These entries are queried from radb.net using whois, you can try my project getting these.
:AS51946 route: 192.100.135.0/24 descr: University of Newcastle upon Tyne descr: Information Systems and Services descr: Claremont Road descr: Newcastle upon Tyne descr: NE1 7RU descr: United Kingdom origin: AS51946 mnt-by: JIPS-NOSC created: 2021-01-14T14:57:51Z last-modified: 2021-01-14T14:57:51Z source: RIPE remarks: **************************** remarks: * THIS OBJECT IS MODIFIED remarks: * Please note that all data that is generally regarded as personal remarks: * data has been removed from this object. remarks: * To view the original object, please query the RIPE Database at: remarks: * http://www.ripe.net/whois remarks: **************************** rpki-ov-state: not_found # No ROAs found, or RPKI validation not enabled for source