These entries are queried from radb.net using whois, you can try my project getting these.
:AS1974 route: 198.200.10.0/23 descr: MMC-SMHC BLK-1 origin: AS1974 mnt-by: MAINT-AS5760 changed: willd [at] staff.gwi.net 20200701 source: ALTDB rpki-ov-state: not_found # No ROAs found, or RPKI validation not enabled for source