diff --git a/ontology/saref4ehaw.ttl b/ontology/saref4ehaw.ttl
index 90f9301b18eb42d3806f9cdda1ba0ed2709f32ad..f4a0b85f513e64f0b6677d1a4d56718256f936ff 100644
--- a/ontology/saref4ehaw.ttl
+++ b/ontology/saref4ehaw.ttl
@@ -242,10 +242,10 @@ s4ehaw:hasLocation rdf:type owl:ObjectProperty ;
                    rdfs:label "has location"@en .
 
 
-###  https://saref.etsi.org/saref4ehaw/hasMeasurement
-s4ehaw:hasMeasurement rdf:type owl:ObjectProperty ;
+###  https://saref.etsi.org/saref4ehaw/hasObservation
+s4ehaw:hasObservation rdf:type owl:ObjectProperty ;
                       rdfs:domain s4ehaw:Data ;
-                      rdfs:range saref:Measurement ;
+                      rdfs:range saref:Observation ;
                       rdfs:comment "Defines the relationship between data that has measurement."@en ;
                       rdfs:label "has measurement"@en .
 
@@ -298,12 +298,12 @@ s4ehaw:hasResponsibleParty rdf:type owl:ObjectProperty ;
                            rdfs:label "has responsible party"@en .
 
 
-###  https://saref.etsi.org/saref4ehaw/hasTimeSeriesMesurement
-s4ehaw:hasTimeSeriesMesurement rdf:type owl:ObjectProperty ;
-                               rdfs:domain s4ehaw:Data ;
-                               rdfs:range s4ehaw:TimeSeriesMeasurement ;
-                               rdfs:comment "Data has time series measurements, a sequence taken at successive equally spaced points in time."@en ;
-                               rdfs:label "has time series measurement"@en .
+###  https://saref.etsi.org/saref4ehaw/hasTimeSeriesObservation
+s4ehaw:hasTimeSeriesObservation rdf:type owl:ObjectProperty ;
+                                rdfs:domain s4ehaw:Data ;
+                                rdfs:range s4ehaw:TimeSeriesObservation ;
+                                rdfs:comment "Data has time series measurements, a sequence taken at successive equally spaced points in time."@en ;
+                                rdfs:label "has time series measurement"@en .
 
 
 ###  https://saref.etsi.org/saref4ehaw/interfaceProtocol
@@ -617,7 +617,7 @@ s4ehaw:hasResult rdf:type owl:DatatypeProperty ;
 
 ###  https://saref.etsi.org/saref4ehaw/hasValues
 s4ehaw:hasValues rdf:type owl:DatatypeProperty ;
-                 rdfs:domain s4ehaw:TimeSeriesMeasurement ;
+                 rdfs:domain s4ehaw:TimeSeriesObservation ;
                  rdfs:range xsd:decimal ;
                  rdfs:comment "A relationship defining the set of values (an ordered array of numbers) of a certain property, e.g., heart rate. Attention: to assure ordering in the serialization format, it is necessary to use either rdf:Seq (RDF/XML) or @list (JSON-LD)."@en ;
                  rdfs:label "has values"@en .
@@ -859,6 +859,10 @@ saref:Measurement rdf:type owl:Class .
 saref:NotifyCommand rdf:type owl:Class .
 
 
+###  https://saref.etsi.org/core/Observation
+saref:Observation rdf:type owl:Class .
+
+
 ###  https://saref.etsi.org/core/Property
 saref:Property rdf:type owl:Class .
 
@@ -1176,9 +1180,9 @@ s4ehaw:ServiceProfile rdf:type owl:Class ;
                       rdfs:label "Service profile"@en .
 
 
-###  https://saref.etsi.org/saref4ehaw/TimeSeriesMeasurement
-s4ehaw:TimeSeriesMeasurement rdf:type owl:Class ;
-                             rdfs:subClassOf saref:Measurement ,
+###  https://saref.etsi.org/saref4ehaw/TimeSeriesObservation
+s4ehaw:TimeSeriesObservation rdf:type owl:Class ;
+                             rdfs:subClassOf saref:Observation ,
                                              [ rdf:type owl:Restriction ;
                                                owl:onProperty s4ehaw:hasFrequency ;
                                                owl:allValuesFrom saref:Property