Summary
h016.blue.pl has one IP number , which also has a corresponding reverse pointer.
dns4.blue.pl point to the same IP.
blue.pl is a domain controlled by two nameservers at
blue.pl themselves. They are on different IP networks. Incoming mail for
blue.pl is handled by one mailserver also at
blue.pl.
blue.pl has one IP number.
h016.blue.pl is hosted on a server in Poland.