mx3.macau.ctm.net has no NS records.
NS records for this zone are defined at macau.ctm.net.
NS records for this zone are defined at macau.ctm.net.
Question and response
Question
dig mx3.macau.ctm.net. NS
Answer
The response has no answer records.
Authority
macau.ctm.net. 3600 SOA vassun1.macau.ctm.net. helpdesk.macau.ctm.net. 2016073723 86400 7200 2419200 3600
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0