These entries are queried from radb.net using whois, you can try my project getting these.
:AS135524 route: 103.221.252.0/22 descr: Dhaka University - Route Object descr: Dhaka University - Route Object origin: AS135524 mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2016-06-05T14:02:52Z source: APNIC rpki-ov-state: valid route: 103.221.252.0/23 descr: Dhaka University - Route Object descr: Dhaka University - Route Object origin: AS135524 mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2016-06-05T14:02:31Z source: APNIC rpki-ov-state: valid route: 103.221.252.0/24 descr: Dhaka University - Route Object origin: AS135524 mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2016-06-05T13:59:31Z source: APNIC rpki-ov-state: valid route: 103.221.253.0/24 descr: Dhaka University - Route Object descr: Dhaka University - Route Object origin: AS135524 mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2016-06-05T14:01:50Z source: APNIC rpki-ov-state: valid route: 103.221.254.0/23 descr: Dhaka University - Route Object descr: Dhaka University - Route Object origin: AS135524 mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2016-06-05T14:02:41Z source: APNIC rpki-ov-state: valid route: 103.221.254.0/24 descr: Dhaka University - Route Object descr: Dhaka University - Route Object origin: AS135524 mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2016-06-05T14:02:06Z source: APNIC rpki-ov-state: valid route: 103.221.255.0/24 descr: Dhaka University - Route Object descr: Dhaka University - Route Object origin: AS135524 mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2016-06-05T14:02:15Z source: APNIC rpki-ov-state: valid route6: 2405:ac80::/32 descr: University of Dhaka - Route Object for IPv6 origin: AS135524 mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2017-12-24T01:12:23Z source: APNIC rpki-ov-state: valid route6: 2405:ac80::/33 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:13Z source: APNIC rpki-ov-state: valid route6: 2405:ac80::/34 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:14Z source: APNIC rpki-ov-state: valid route6: 2405:ac80::/35 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:15Z source: APNIC rpki-ov-state: valid route6: 2405:ac80::/36 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:15Z source: APNIC rpki-ov-state: valid route6: 2405:ac80::/48 descr: Dhaka University - Route Object origin: AS135524 mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-15T15:43:36Z source: APNIC rpki-ov-state: valid route6: 2405:ac80:1000::/36 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:16Z source: APNIC rpki-ov-state: valid route6: 2405:ac80:2000::/35 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:16Z source: APNIC rpki-ov-state: valid route6: 2405:ac80:2000::/36 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:17Z source: APNIC rpki-ov-state: valid route6: 2405:ac80:3000::/36 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:17Z source: APNIC rpki-ov-state: valid route6: 2405:ac80:4000::/34 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:18Z source: APNIC rpki-ov-state: valid route6: 2405:ac80:4000::/35 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:18Z source: APNIC rpki-ov-state: valid route6: 2405:ac80:4000::/36 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:19Z source: APNIC rpki-ov-state: valid route6: 2405:ac80:5000::/36 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:19Z source: APNIC rpki-ov-state: valid route6: 2405:ac80:6000::/35 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:20Z source: APNIC rpki-ov-state: valid route6: 2405:ac80:6000::/36 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:21Z source: APNIC rpki-ov-state: valid route6: 2405:ac80:7000::/36 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:21Z source: APNIC rpki-ov-state: valid route6: 2405:ac80:8000::/33 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:22Z source: APNIC rpki-ov-state: valid route6: 2405:ac80:8000::/34 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:22Z source: APNIC rpki-ov-state: valid route6: 2405:ac80:8000::/35 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:23Z source: APNIC rpki-ov-state: valid route6: 2405:ac80:8000::/36 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:23Z source: APNIC rpki-ov-state: valid route6: 2405:ac80:9000::/36 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:24Z source: APNIC rpki-ov-state: valid route6: 2405:ac80:a000::/35 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:25Z source: APNIC rpki-ov-state: valid route6: 2405:ac80:a000::/36 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:25Z source: APNIC rpki-ov-state: valid route6: 2405:ac80:b000::/36 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:26Z source: APNIC rpki-ov-state: valid route6: 2405:ac80:c000::/34 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:26Z source: APNIC rpki-ov-state: valid route6: 2405:ac80:c000::/35 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:27Z source: APNIC rpki-ov-state: valid route6: 2405:ac80:c000::/36 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:27Z source: APNIC rpki-ov-state: valid route6: 2405:ac80:d000::/36 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:28Z source: APNIC rpki-ov-state: valid route6: 2405:ac80:e000::/35 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:29Z source: APNIC rpki-ov-state: valid route6: 2405:ac80:e000::/36 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:29Z source: APNIC rpki-ov-state: valid route6: 2405:ac80:f000::/36 origin: AS135524 descr: university of dhaka Nilkhet Road, Dhaka, Bangladesh mnt-by: MAINT-UNIVERSITYOFDHAKA-BD last-modified: 2019-10-16T13:02:30Z source: APNIC rpki-ov-state: valid