spf.verizonwireless.com has no NS records.
NS records for this zone are defined at verizonwireless.com.
NS records for this zone are defined at verizonwireless.com.
Question and response
Question
dig spf.verizonwireless.com. NS
Answer
The response has no answer records.
Authority
verizonwireless.com. 900 SOA ns-twbg.verizonwireless.com. dnsadmin.verizonwireless.com. 25719 1800 600 604800 900
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0