mx1.internetx.com has no NS records.
NS records for this zone are defined at internetx.com.
NS records for this zone are defined at internetx.com.
Question and response
Question
dig mx1.internetx.com. NS
Answer
The response has no answer records.
Authority
internetx.com. 432000 SOA nsa.domain-robot.org. domain-support.internetx.de. 2026021700 43200 7200 1209600 432000
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0