4.0-29.202.131.202.in-addr.arpa has no NS records.
NS records for this zone are defined at 0-29.202.131.202.in-addr.arpa.
NS records for this zone are defined at 0-29.202.131.202.in-addr.arpa.
Question and response
Question
dig 4.0-29.202.131.202.in-addr.arpa. NS
Answer
The response has no answer records.
Authority
0-29.202.131.202.in-addr.arpa. 86400 SOA ns.bit-isle.co.jp. root.ns.bit-isle.co.jp. 2008052200 3600 1800 43200 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0