pop3.wind.net.do has no NS records.
NS records for this zone are defined at wind.net.do.
NS records for this zone are defined at wind.net.do.
Question and response
Question
dig pop3.wind.net.do. NS
Answer
The response has no answer records.
Authority
wind.net.do. 3600 SOA ns2.wind.com.do. hostmaster.wind.com.do. 2011113029 900 600 86400 3600
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0