DOC: add hint on wildcard

src/doc/concepts.rst

@@ -85,7 +85,9 @@ we can check whether a Record with the parent "Project" is referencing the "Expe
 Record. If that is the case, this reference is part of the identifiable for the "Experiment"
 Record. Note, that if there are multiple Records with the appropriate parent (e.g.
 multiple "Project" Records in the above example) it will be required that all of them
-reference the object to be identified.
+reference the object to be identified. You can also use the wildcard "*" as
+RecordType name in the configuration which will only require, that ANY Record
+references the Record at hand.
 
 
 Identified Records