alt2.aspmx.l.google.com.intgdc.com has no NS records.
NS records for this zone are defined at intgdc.com.
NS records for this zone are defined at intgdc.com.
Question and response
Question
dig alt2.aspmx.l.google.com.intgdc.com. NS
Answer
The response has no answer records.
Authority
intgdc.com. 60 SOA dns1.p07.nsone.net. hostmaster.nsone.net. 1653937827 600 300 1209600 60
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0