Apex domains cannot have CNAME records.
Question and response
Question
dig specto.exlibrisgroup.com. NS
Answer
specto.exlibrisgroup.com. 3 NS dns2.p04.nsone.net.
specto.exlibrisgroup.com. 3 NS dns3.p04.nsone.net.
specto.exlibrisgroup.com. 3 NS dns4.p04.nsone.net.
specto.exlibrisgroup.com. 3 NS ns0-mnm.dc01.hosted.exlibrisgroup.com.
specto.exlibrisgroup.com. 3 NS ns0-mnm.dc04.hosted.exlibrisgroup.com.
specto.exlibrisgroup.com. 3 NS dns1.p04.nsone.net.
Authority
The response has no authority records.
Additional
dns1.p04.nsone.net. 3 A 198.51.44.4
dns2.p04.nsone.net. 3 A 198.51.45.4
dns3.p04.nsone.net. 3 A 198.51.44.68
dns4.p04.nsone.net. 3 A 198.51.45.68
dns1.p04.nsone.net. 3 AAAA 2620:4d:4000:6259:7:4:0:1
dns2.p04.nsone.net. 3 AAAA 2a00:edc0:6259:7:4:0:0:2
dns3.p04.nsone.net. 3 AAAA 2620:4d:4000:6259:7:4:0:3
dns4.p04.nsone.net. 3 AAAA 2a00:edc0:6259:7:4:0:0:4
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0