https://wiki.debian.org/Bind9

https://intodns.com/

https://dnsviz.net/d/bdcom.com/dnssec/

bind.tar.gz

https://www.youtube.com/watch?v=1xkp8pLDqn0

https://github.com/shamimrezasohag/DSAT-DNSSecurityAnalysisTool

https://www.vedbex.com/subdomain-finder