questions about DNS notify

[Ken Peng]

Hi,

 From a DNS book I saw,

The DNS notify message will be received by all severs that are listed in 
the NS records for the
given zone. The server indicated inthe SOA record is not informed since 
it is presumed that it is
this server that generates the messages. Some implementations enable 
master server administrators
to add other IP addresses of other name servers to the set of the 
existing ones. The set of servers
for which the DNS Notify is generated is called the Notify Set.

For example, I have this zone,

$ cat zone.com.any.db
$ORIGIN .
$TTL 3600       ; 1 hour
zone.com                IN SOA  dwdns1.nsbeta.info. hostmaster.xxx.com. (
                                 1804       ; serial
                                 7200       ; refresh (2 hours)
                                 1800       ; retry (30 minutes)
                                 604800     ; expire (1 week)
                                 300        ; minimum (5 minutes)
                                 )
                         NS      dwdns1.nsbeta.info.
                         NS      dwdns2.nsbeta.info.


Before master send notify to slaves, where will master query from, to 
get the IP addresses for those slaves?
It's from the auth-nameservers of nsbeta.info, or from the glue records 
in the info domain, or just from the LDNS?
I am totally confused about this.
I wish I have described the question clearly, :)
Thanks in advance.

-- 
   B. Regards,
   Ken Peng - ken at cloud-china.org