diff --git a/README.md b/README.md
index 56b60d7..d907256 100644
--- a/README.md
+++ b/README.md
@@ -162,8 +162,42 @@ Via display names (introduced in V3.0RC01 Referable/displayName, it is also poss
Note: It is requested that the idShort of a non-identifiable is unique in its name space (for example in a Submodel or in a SubmodelElementCollection). This is not requested for the display names!
-
-
+**[How to reference an ECLASS application or classification class](#id45)**
+
+Referencing of application and classification classes is no different to referencing the ECLASS property definition.
+Since classification and application classes correspond to a set of properties they can be used to describe the semantics of a complete submodel or of an SubmodelElementCollection.
+
+Please be aware: to be completeley unambiguous it is either necessary to model the complete hierarchy in the submodel or by using a semanticId with more than one IRDI. The keys in the reference are ordered.
+
+Example:
+
+* Application Class: 0173-1#01-AAB572#006 Electric engineering, automation, process control engineering
+* Classification Level 1: 0173-1#01-AAB583#008 Electrical drive
+* Classification Level 2: 0173-1#01-AJZ695#008 Servo motor
+* Classification Level 3: 0173-1#01-AJZ696#015 Servo asynchronous motor
+
+For example the semanticId of a submodel containing the properties for the asynchronous servo motor without any further hierarchical modelling would be:
+
+
+
+
+
+
+ 0173-1#01-AAB572#006
+
+ 0173-1#01-AAB583#008
+
+ 0173-1#01-AJZ695#008
+
+ 0173-1#01-AJZ696#015
+
+
+
+
+
+
+
+(Answered: 2021-01-11)
## Asset Administration Shell in Detail Series