Unable to find any PTR-records for the specified domain/ip :(
Log
+000
Resolving PTR record of '18.68.65.0'
+137
ERRNo PTR record availible DNS server 'x4.amazonaws.org' raised an NotExistentDomain error, while beeing queried for PTR-records on domain '0.65.68.18.in-addr.arpa'.