These entries are queried from radb.net using whois, you can try my project getting these.
:AS23634 route: 192.50.43.0/24 descr: E.DNS.JP - One of the JP DNS Servers origin: AS23634 mnt-by: RENATER-MNT remarks: changed: rensvp [at] renater.fr 20100823 created: 2010-08-24T09:52:03Z last-modified: 2018-09-04T16:20:03Z source: RIPE-NONAUTH 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 route: 192.50.43.0/24 descr: E.DNS.JP -- one of the JP DNS Servers origin: AS23634 mnt-by: MAINT-AS2500 changed: kato [at] wide.ad.jp 20030613 source: RADB last-modified: 2023-11-13T15:39:33Z rpki-ov-state: not_found # No ROAs found, or RPKI validation not enabled for source route6: 2001:200:c000::/35 origin: AS23634 descr: WIDE Murai Lab Keio University 5322 Endo, Fujisawa-shi mnt-by: MAINT-JP-WIDE last-modified: 2017-08-31T02:17:49Z source: APNIC rpki-ov-state: valid route6: 2001:200:c000::/35 descr: WIDE Project origin: AS23634 mnt-by: MAINT-AS2500 changed: kato [at] wide.ad.jp 20070625 source: RADB last-modified: 2023-11-13T15:39:41Z rpki-ov-state: valid