diff --git a/ontology/saref4inma.ttl b/ontology/saref4inma.ttl
index 396dc8bac70d9a876d24a06af64078e5dc8acf27..d0e3ca36270b511c37d902bb5ebd31b292d95766 100644
--- a/ontology/saref4inma.ttl
+++ b/ontology/saref4inma.ttl
@@ -11,7 +11,6 @@
 
 <https://saref.etsi.org/saref4inma/> rdf:type owl:Ontology ;
                                       owl:versionIRI <https://saref.etsi.org/saref4inma/v2.1.1/> ;
-                                      owl:imports <https://saref.etsi.org/core/v3.2.1/> ;
                                       <http://purl.org/dc/terms/contributor> <http://purl.org/net/mpoveda> ,
                                                                              <https://www.linkedin.com/in/matthijs-punter-0799902> ;
                                       <http://purl.org/dc/terms/created> "2015-03-29"^^xsd:date ;
@@ -92,6 +91,14 @@ owl:maxQualifiedCardinality rdf:type owl:AnnotationProperty .
 owl:versionIRI rdf:type owl:AnnotationProperty .
 
 
+#################################################################
+#    Datatypes
+#################################################################
+
+###  http://www.w3.org/2001/XMLSchema#date
+xsd:date rdf:type rdfs:Datatype .
+
+
 #################################################################
 #    Object Properties
 #################################################################
@@ -104,12 +111,12 @@ saref:hasFunction rdf:type owl:ObjectProperty .
 saref:hasState rdf:type owl:ObjectProperty .
 
 
-###  https://saref.etsi.org/core/makesMeasurement
-saref:makesMeasurement rdf:type owl:ObjectProperty .
+###  https://saref.etsi.org/core/madeExecution
+saref:madeExecution rdf:type owl:ObjectProperty .
 
 
-###  https://saref.etsi.org/core/measuresProperty
-saref:measuresProperty rdf:type owl:ObjectProperty .
+###  https://saref.etsi.org/core/observes
+saref:observes rdf:type owl:ObjectProperty .
 
 
 ###  https://saref.etsi.org/saref4inma/belongsToCategory
@@ -342,8 +349,8 @@ saref:FeatureOfInterest rdf:type owl:Class .
 saref:Function rdf:type owl:Class .
 
 
-###  https://saref.etsi.org/core/Measurement
-saref:Measurement rdf:type owl:Class .
+###  https://saref.etsi.org/core/Observation
+saref:Observation rdf:type owl:Class .
 
 
 ###  https://saref.etsi.org/core/Property
@@ -374,7 +381,7 @@ saref:State rdf:type owl:Class .
 
 ###  https://saref.etsi.org/saref4inma/ActualMeasurement
 s4inma:ActualMeasurement rdf:type owl:Class ;
-                         rdfs:subClassOf s4inma:Measurement ;
+                         rdfs:subClassOf saref:Observation ;
                          owl:disjointWith s4inma:ExpectedMeasurement ;
                          rdfs:comment "Describes whether the measurement is actually measured during the production process. Disjoint with ExpectedMeasurement." ;
                          rdfs:label "Actual measurement"@en .
@@ -414,7 +421,7 @@ s4inma:Batch rdf:type owl:Class ;
 
 ###  https://saref.etsi.org/saref4inma/ExpectedMeasurement
 s4inma:ExpectedMeasurement rdf:type owl:Class ;
-                           rdfs:subClassOf s4inma:Measurement ;
+                           rdfs:subClassOf saref:Observation ;
                            rdfs:comment "Describes whether the measurement is expected (i.e., planned before the production process). Disjoint with ActualMeasurement." ;
                            rdfs:label "Expected measurement"@en .
 
@@ -585,13 +592,6 @@ s4inma:MaterialCategory rdf:type owl:Class ;
                         rdfs:label "Material category"@en .
 
 
-###  https://saref.etsi.org/saref4inma/Measurement
-s4inma:Measurement rdf:type owl:Class ;
-                   rdfs:subClassOf saref:Measurement ;
-                   rdfs:comment "A subclass of saref:Measurement that represents the measured value made over a property. It is also linked to the unit of measure in which the value is expressed and the timestamp of the measurement. The saref4imna:Measurement can be linked to individual Batches or Items. Moreover, the Measurement can be an ExpectedMeasurement (i.e. the value which is planned) or the ActualMeasurement (i.e. the value measured during production), which enables to check for deviations between the planned and actual values." ;
-                   rdfs:label "Measurement"@en .
-
-
 ###  https://saref.etsi.org/saref4inma/ProductionEquipment
 s4inma:ProductionEquipment rdf:type owl:Class ;
                            rdfs:subClassOf saref:Device ,
@@ -605,11 +605,11 @@ s4inma:ProductionEquipment rdf:type owl:Class ;
                                              owl:allValuesFrom saref:State
                                            ] ,
                                            [ rdf:type owl:Restriction ;
-                                             owl:onProperty saref:makesMeasurement ;
-                                             owl:allValuesFrom s4inma:Measurement
+                                             owl:onProperty saref:madeExecution ;
+                                             owl:allValuesFrom saref:Observation
                                            ] ,
                                            [ rdf:type owl:Restriction ;
-                                             owl:onProperty saref:measuresProperty ;
+                                             owl:onProperty saref:observes ;
                                              owl:allValuesFrom saref:Property
                                            ] ,
                                            [ rdf:type owl:Restriction ;