shell:$ nslookup -timeout=2 -retry=1 'ksef.mf.gov.pl'
Server:		1.1.1.1
Address:	1.1.1.1#53

Non-authoritative answer:
ksef.mf.gov.pl	canonical name = nudnsjz.ng.impervadns.net.
Name:	nudnsjz.ng.impervadns.net
Address: 45.60.74.103