These entries are queried from radb.net using whois, you can try my project getting these.
:AS139674 route: 103.147.56.0/23 descr: SIL-BD Network origin: AS139674 mnt-by: MAINT-BD-SIL last-modified: 2020-01-02T03:33:34Z source: APNIC rpki-ov-state: valid route: 103.147.56.0/24 descr: SIL-BD Network for BGP Announcement origin: AS139674 mnt-by: MAINT-BD-SIL last-modified: 2020-01-02T03:36:52Z source: APNIC rpki-ov-state: valid route: 103.147.57.0/24 descr: SIL-BD Network for BGP Announcement origin: AS139674 mnt-by: MAINT-BD-SIL last-modified: 2020-01-02T03:39:57Z source: APNIC rpki-ov-state: valid