In a single DCI instance it is able to place several dci-spec structures as well as to include other DCI files.
This offer the possibility to cascade DCI-specifications.
E.g. some basic checks (e.g. the ASAM MCD basetypes) will be included. Company specific or development status related checks can place in this instance.
There are two possibilities to address the dci instance
 
with an unified resource locator - <dci-include-uri>
 
with the <dci-spec-ref> element.