These entries are queried from radb.net using whois, you can try my project getting these.
:AS393308 route: 198.151.137.0/24 descr: City of Iowa City Iowa City, Iowa, USA origin: AS393308 remarks: City of Iowa City for backup transit via uiowa mnt-by: MAINT-UIOWA changed: jay-ford [at] uiowa.edu 20140130 #17:14:08Z source: RADB last-modified: 2023-11-13T15:45:59Z rpki-ov-state: not_found # No ROAs found, or RPKI validation not enabled for source