diff --git a/ontology/saref4agri.ttl b/ontology/saref4agri.ttl
index 1dec96f20bb248652ccf28923bf9e1ecb2c588a3..64d547747f0afe5ef0ffea1a02294aee16207891 100644
--- a/ontology/saref4agri.ttl
+++ b/ontology/saref4agri.ttl
@@ -137,14 +137,6 @@ wgs84:long rdf:type owl:ObjectProperty ;
   rdfs:domain wgs84:SpatialThing .
 
 
-###  http://www.w3.org/2004/02/skos/core#definition
-<http://www.w3.org/2004/02/skos/core#definition> rdf:type owl:AnnotationProperty .
-
-
-###  http://www.w3.org/2004/02/skos/core#prefLabel
-<http://www.w3.org/2004/02/skos/core#prefLabel> rdf:type owl:AnnotationProperty .
-
-
 ###  http://xmlns.com/foaf/0.1/based_near
 foaf:based_near rdf:type owl:ObjectProperty .
 
@@ -581,30 +573,6 @@ sameThing(P1, P2) :- type(P1, Point), type(P2, Point), spaciallyIntersects(P1, P
   rdfs:isDefinedBy <http://www.w3.org/2003/01/geo/wgs84_pos#> ;
   rdfs:label "Point"@en .
 
-
-###  http://www.w3.org/2006/time#Instant
-time:Instant rdf:type owl:Class ;
-  rdfs:subClassOf time:TemporalEntity ;
-  rdfs:comment "A temporal entity with zero extent or duration"@en ;
-  rdfs:isDefinedBy <http://www.w3.org/2006/time#> ;
-  rdfs:label "Instant"@en .
-
-
-###  http://www.w3.org/2006/time#Interval
-time:Interval rdf:type owl:Class ;
-  rdfs:subClassOf time:TemporalEntity ;
-  rdfs:comment "A temporal entity with an extent or duration"@en ;
-  rdfs:isDefinedBy <http://www.w3.org/2006/time#> ;
-  rdfs:label "Time interval"@en .
-
-
-###  http://www.w3.org/2006/time#TemporalEntity
-time:TemporalEntity rdf:type owl:Class ;
-  rdfs:comment "A temporal interval or instant."@en ;
-  rdfs:isDefinedBy <http://www.w3.org/2006/time#> ;
-  rdfs:label "Temporal entity"@en .
-
-
 ###  http://www.w3.org/ns/sosa/Platform
 sosa:Platform rdf:type owl:Class ;
   rdfs:comment "A Platform is an entity that hosts other entities, particularly Sensors, Actuators, Samplers, and other Platforms (definition taken from http://www.w3.org/ns/sosa/Platform)"@en ;
@@ -624,14 +592,16 @@ ssn:System rdf:type owl:Class ;
   rdfs:isDefinedBy <http://www.w3.org/ns/ssn/> ;
   rdfs:label "System"@en .
 
-
+###  http://www.w3.org/2006/time
+time:Interval a owl:Class ;
+  rdfs:isDefinedBy time: ;
+.
 
 ###  http://xmlns.com/foaf/0.1/Person
 foaf:Person rdf:type owl:Class ;
   rdfs:subClassOf foaf:Agent ;
   rdfs:label "Person"@en .
 
-
 ###  https://saref.etsi.org/saref4agri/Animal
 s4agri:Animal rdf:type owl:Class ;
   rdfs:subClassOf saref:FeatureOfInterest ,
@@ -745,7 +715,7 @@ s4agri:Deployment rdf:type owl:Class ;
     ] ,
     [ rdf:type owl:Restriction ;
       owl:onProperty s4agri:hasDeploymentPeriod ;
-      owl:someValuesFrom time:TemporalEntity
+      owl:someValuesFrom time:Interval
     ] ,
     [ rdf:type owl:Restriction ;
       owl:onProperty s4agri:isDeployedAtSpace ;