How to check the glue records stored for a given domain.
Let's say that it is a .org domain, first of all query for the nameserver of the TLD:
dig +short org. NS
than query one TLD about the domain:
dig +norec @b2.org.afilias-nst.org. rigacci.org. NS
check the ADDITIONAL SECTION into the answer:
;; AUTHORITY SECTION: rigacci.org. 86400 IN NS ns1.rigacci.org. rigacci.org. 86400 IN NS ns2.rigacci.org. ;; ADDITIONAL SECTION: ns1.rigacci.org. 86400 IN A 92.222.46.168 ns2.rigacci.org. 86400 IN A 176.9.39.130