Unable to find any PTR-records for the specified domain/ip :(
Log
+000
Resolving PTR record of '147.189.20.0'
+208
ERRNo PTR record availible DNS server 'y.arin.net' raised an NotExistentDomain error, while beeing queried for PTR-records on domain '0.20.189.147.in-addr.arpa'.