How to sub-delegate a reverse zone [KB1240]

How to sub-delegate a reverse zone [KB1240]: "For example say you have IP addresses 11.22.33.0/24 (11.22.33.0 to 11.22.33.255) and you want to sub-delegate reverse DNS for 11.22.33.64/30 (11.22.33.64 to 11.22.33.67) to your customer's DNS servers.
Then in your "33.22.11.in-addr.arpa" zone, you would add an NS-record for "64/30.33.22.11.in-addr.arpa" for each of your customers's DNS servers, and a CNAME-record for "XX.33.22.11.in-addr.arpa" pointing to "XX.64/30.33.22.11.in-addr.arpa" for each of the IP addresses in the customer's IP range where XX is the last segment of each IP address like this:

NS: 64/30.33.22.11.in-addr.arpa -> ns1.customer.com
NS: 64/30.33.22.11.in-addr.arpa -> ns2.customer.com
CNAME: 64.33.22.11.in-addr.arpa -> 64.64/30.33.22.11.in-addr.arpa
CNAME: 65.33.22.11.in-addr.arpa -> 65.64/30.33.22.11.in-addr.arpa
CNAME: 66.33.22.11.in-addr.arpa -> 66.64/30.33.22.11.in-addr.arpa
CNAME: 67.33.22.11.in-addr.arpa -> 67.64/30.33.22.11.in-addr.arpa"

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