Apex domains cannot have CNAME records.
Question and response
Question
dig canon.net. NS
Answer
canon.net. 4 NS ns1.jp.canon.com.
canon.net. 4 NS ns2.canon.net.
canon.net. 4 NS ns2.jp.canon.com.
canon.net. 4 NS ns1.canon.net.
canon.net. 4 NS ns3.jp.canon.com.
canon.net. 4 NS ns3.canon.net.
Authority
The response has no authority records.
Additional
ns1.jp.canon.com. 4 A 208.94.148.13
ns1.canon.net. 4 A 157.7.32.53
ns2.jp.canon.com. 4 A 208.80.124.13
ns2.canon.net. 4 A 157.7.33.53
ns3.jp.canon.com. 4 A 208.80.126.13
ns3.canon.net. 4 A 157.7.34.53
ns1.jp.canon.com. 4 AAAA 2600:1800:5:0:0:0:0:1
ns1.canon.net. 4 AAAA 2400:8500:3300:0:0:0:0:53
ns2.jp.canon.com. 4 AAAA 2600:1801:6:0:0:0:0:1
ns2.canon.net. 4 AAAA 2400:8500:3000:0:0:0:0:53
ns3.canon.net. 4 AAAA 2400:8500:3fff:0:0:0:0:53
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0