Apex domains cannot have CNAME records.
Question and response
Question
dig rudolfnureyev.org. NS
Answer
rudolfnureyev.org. 5 NS ns-493.awsdns-61.com.
rudolfnureyev.org. 5 NS ns-226.awsdns-28.com.
rudolfnureyev.org. 5 NS ns-1201.awsdns-22.org.
rudolfnureyev.org. 5 NS ns-818.awsdns-38.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0