These entries are queried from radb.net using whois, you can try my project getting these.
:AS-RTBHOUSE-SIN as-set: AS-RTBHOUSE-SIN descr: tech-c: RHA2-AP admin-c: RHA2-AP mnt-by: MAINT-RTBHOUSE-SG last-modified: 2019-05-14T09:33:13Z members: AS138552 source: APNIC