Unable to find any PTR-records for the specified domain/ip :(
Log
+000
Resolving PTR record of '15.197.18.0'
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ERRNo PTR record availible DNS server 'pdns1.ultradns.net' raised an NotExistentDomain error, while beeing queried for PTR-records on domain '0.18.197.15.in-addr.arpa'.