mail.pbw.pl has no NS records.
NS records for this zone are defined at pbw.pl.
NS records for this zone are defined at pbw.pl.
Question and response
Question
dig www.pbw.pl. NS
Answer
The response has no answer records.
Authority
pbw.pl. 3600 SOA ns1.premium.pl. admin.premium.pl. 918294251 14400 7200 2419200 3600
Additional
. 0 OPT ; payload 1220, xrcode 0, version 0, flags 0