diff --git a/ontology/saref4bldg.ttl b/ontology/saref4bldg.ttl
index 18ce3b9224289d2e4676fc9fcba2519a5532402b..7be11ce78a66c0213486e992cbe0226dcfdb2382 100644
--- a/ontology/saref4bldg.ttl
+++ b/ontology/saref4bldg.ttl
@@ -19,7 +19,7 @@
 	dc:title "SAREF extension for building devices"@en ;
 	dc:publisher <http://www.oeg-upm.net/> ;
 	vann:preferredNamespacePrefix "s4bldg" ;
-	dc:description "This ontology extends the SAREF ontology for the building domain by defining building devices and how they are located in a building. This extension is based on the ISO 16739:2013 Industry Foundation Classes (IFC) standard for data sharing in the construction and facility management industries. The descriptions of the classes and properties extracted from IFC have been taken from the IFC documentation."@en .
+	dc:description "This ontology extends the SAREF ontology for the building domain by defining building devices and how they are located in a building. This extension is based on the ISO 16740:2013 Industry Foundation Classes (IFC) standard for data sharing in the construction and facility management industries. The descriptions of the classes and properties extracted from IFC have been taken from the IFC documentation."@en .
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