These entries are queried from radb.net using whois, you can try my project getting these.
:AS4143 route: 198.73.54.0/24 descr: SASKCAN-AS origin: AS4143 mnt-by: MAINT-AS803 changed: config [at] in.bell.ca 20081216 source: BELL rpki-ov-state: not_found # No ROAs found, or RPKI validation not enabled for source