ipam.tue.nl has no NS records.
NS records for this zone are defined at tue.nl.
NS records for this zone are defined at tue.nl.
Question and response
Question
dig ipam.tue.nl. NS
Answer
The response has no answer records.
Authority
tue.nl. 900 SOA ipam.tue.nl. hostmaster.tue.nl. 34672 10800 3600 2419200 900
Additional
. 0 OPT ; payload 1220, xrcode 0, version 0, flags 0