diff --git a/ontology/saref4ehaw.ttl b/ontology/saref4ehaw.ttl
index c5f587447e9b5d94d59544bd8ff13fe121c1a9f8..c128b767aeeaf2a43b7a4c1d57dbb11f059a6f0e 100644
--- a/ontology/saref4ehaw.ttl
+++ b/ontology/saref4ehaw.ttl
@@ -5,7 +5,6 @@
 @prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
 @prefix foaf: <http://xmlns.com/foaf/0.1/> .
 @prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
-@prefix skos: <http://www.w3.org/2004/02/skos/core#> .
 @prefix vann: <http://purl.org/vocab/vann/> .
 @prefix voaf: <http://purl.org/vocommons/voaf#> .
 @prefix saref: <https://saref.etsi.org/saref#> .