DOCS: SOA docs should cite BIND doc

docs/_functions/domain/SOA.md

@@ -23,8 +23,9 @@ D("example.com", REG_THIRDPARTY, DnsProvider("DNS_BIND"),
 {%endhighlight%}
 {% include endExample.html %}
 
-
 ## Notes:
 
 * The serial number is managed automatically.  It isn't even a field in `SOA()`.
 * Most providers automatically generate SOA records.  They will ignore any `SOA()` statements.
+
+There is more info about SOA in the documentation for the [BIND provider]({{site.github.url}}/providers/bind).