These entries are queried from radb.net using whois, you can try my project getting these.
:AS138146 route: 103.121.60.0/24 descr: North Bengal Online origin: AS138146 mnt-by: MAINT-NORTHBENGALONLINE-BD last-modified: 2018-08-18T05:28:41Z source: APNIC rpki-ov-state: valid route: 103.121.61.0/24 descr: North Bengal Online origin: AS138146 mnt-by: MAINT-NORTHBENGALONLINE-BD last-modified: 2018-08-18T05:28:50Z source: APNIC rpki-ov-state: valid route: 103.121.62.0/24 descr: North Bengal Online origin: AS138146 mnt-by: MAINT-NORTHBENGALONLINE-BD last-modified: 2018-08-18T05:29:00Z source: APNIC rpki-ov-state: valid route: 103.121.63.0/24 descr: North Bengal Online origin: AS138146 mnt-by: MAINT-NORTHBENGALONLINE-BD last-modified: 2018-08-18T05:29:16Z source: APNIC rpki-ov-state: valid