cc nameserver records in .com zone

[Matthew SAMS]

Greetings,

I believe that all authoritative name servers
in the .com domain must have glue records
in the .com zone. That is, if the authoritative
nameservers for foo.com are ns1.foo.com and
ns2.foo.com, there must be two records in the
.com zone for each of those nameservers. An A 
record and an NS record. For example,

foo in ns ns1.foo.com.
ns1.foo.com. in a 127.0.0.1

Please correct me if I'm wrong.

So what happens when the authoritative nameservers
for a domain are from a different parent tld.
For example, the authoritative nameservers for
foo.com are ns1.foo.ca and ns2.foo.ca.

Are only NS records required and the A record
lookup will be forwarded to the .ca root servers?
Perhaps forwarded is a poor choice of words but 
it's the only one I can think of at this hour.

Thanks,
-Matthew