These entries are queried from radb.net using whois, you can try my project getting these.
:AS57124 route: 141.105.144.0/21 descr: Gemeente Maastricht origin: AS57124 member-of: AS57124:RS-OWN-IPV4-PREFIXES notify: netwerk [at] maastricht.nl mnt-by: GM11595-MNT created: 2011-07-30T19:56:01Z last-modified: 2011-08-02T06:22:31Z 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: valid route: 185.117.76.0/22 descr: Gemeente Maastricht origin: AS57124 notify: netwerk [at] maastricht.nl member-of: AS57124:RS-OWN-IPV4-PREFIXES mnt-by: GM11595-MNT created: 2015-09-18T09:45:26Z last-modified: 2015-09-18T09:45:26Z 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: valid route6: 2a01:8980::/32 descr: Gemeente Maastricht origin: AS57124 member-of: AS57124:RS-OWN-IPV6-PREFIXES notify: netwerk [at] maastricht.nl mnt-by: GM11595-MNT created: 2011-07-30T19:59:26Z last-modified: 2011-08-02T06:29:42Z 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: valid