These entries are queried from radb.net using whois, you can try my project getting these.
:AS136439 route: 103.138.77.0/24 origin: AS136439 descr: Defence Science Technology Agency 1 Depot Road, Singapore 109679 mnt-by: MAINT-DSTA-DMZ-SG last-modified: 2019-07-12T13:30:51Z source: APNIC rpki-ov-state: valid