These entries are queried from radb.net using whois, you can try my project getting these.
:AS6056 route: 137.146.0.0/16 descr: Colby College origin: AS6056 mnt-by: MAINT-TVC changed: dan [at] firstlight.net 20151202 source: ALTDB rpki-ov-state: not_found # No ROAs found, or RPKI validation not enabled for source