ref.addressbook -> ref.addressgroup
@@ -151,7 +151,7 @@ A specification for IPv4 addresses. An `ipSpec` is a string with the following s
```
ipSpec =
- ref.addressbook(<group=string>,<book=string>)
+ ref.addressgroup(<group=string>,<book=string>)
| ofLocation(<locationSpec>)
| <ipv4spec>
| <ipv4spec> - <ipv4spec>
