ip.btc-net.bg has no NS records.
NS records for this zone are defined at btc-net.bg.
NS records for this zone are defined at btc-net.bg.
Question and response
Question
dig ip.btc-net.bg. NS
Answer
The response has no answer records.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0