Unable to find any PTR-records for the specified domain/ip :(
Log
+000
Resolving PTR record of '209.139.0.0'
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ERRNo PTR record availible DNS server 'auth2.ns.gin.ntt.net' raised an NotExistentDomain error, while beeing queried for PTR-records on domain '0.0.139.209.in-addr.arpa'.