Ontology-Extensions.md

 # OiN 
 ## Extension for source Classes:
+*BEWARE*:
+- `ecrm` version might differ
+- Also `E22` might be called `Human-Made_Object`
+
 ```SPARQL
 PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
 PREFIX owl: <http://www.w3.org/2002/07/owl#>