diff --git a/vocabularies/facs/instruments/index.ttl b/vocabularies/facs/instruments/index.ttl
index c70c80aae5f886c9d0762c6abd02fc9e77758770..8a3b811452784af8f60812af33e840d3e47186ef 100644
--- a/vocabularies/facs/instruments/index.ttl
+++ b/vocabularies/facs/instruments/index.ttl
@@ -4,7 +4,6 @@
 @prefix dcterms: <http://purl.org/dc/terms/> .
 
 
-
 <http://purl.org/coscine/vocabularies/facs/instruments>
 dcterms:license <http://spdx.org/licenses/MIT> ;
 dcterms:publisher <https://itc.rwth-aachen.de/> ;
@@ -13,31 +12,31 @@ dcterms:title "Instruments"@en ;
 rdfs:label "Instruments"@en, "Instrumente"@de
 .
 
-<http://purl.org/coscine/vocabularies/facs/instruments#0>;
+<http://purl.org/coscine/vocabularies/facs/instruments#0> a <http://purl.org/coscine/vocabularies/facs/instruments#0> ;
 rdfs:label "BD LSRFortessa"@de , "BD LSRFortessa"@en ;
 rdfs:subClassOf <http://purl.org/coscine/vocabularies/facs/instruments>
 .
 
 
-<http://purl.org/coscine/vocabularies/facs/instruments#1>;
+<http://purl.org/coscine/vocabularies/facs/instruments#1> a <http://purl.org/coscine/vocabularies/facs/instruments#1> ;
 rdfs:label "BD Canto"@de , "BD Canto"@en ;
 rdfs:subClassOf <http://purl.org/coscine/vocabularies/facs/instruments>
 .
 
 
-<http://purl.org/coscine/vocabularies/facs/instruments#2>;
+<http://purl.org/coscine/vocabularies/facs/instruments#2> a <http://purl.org/coscine/vocabularies/facs/instruments#2> ;
 rdfs:label "BD Aria"@de , "BD Aria"@en ;
 rdfs:subClassOf <http://purl.org/coscine/vocabularies/facs/instruments>
 .
 
 
-<http://purl.org/coscine/vocabularies/facs/instruments#3>;
+<http://purl.org/coscine/vocabularies/facs/instruments#3> a <http://purl.org/coscine/vocabularies/facs/instruments#3> ;
 rdfs:label "Cytek Aurora"@de , "Cytek Aurora"@en ;
 rdfs:subClassOf <http://purl.org/coscine/vocabularies/facs/instruments>
 .
 
 
-<http://purl.org/coscine/vocabularies/facs/instruments#4>;
+<http://purl.org/coscine/vocabularies/facs/instruments#4> a <http://purl.org/coscine/vocabularies/facs/instruments#4> ;
 rdfs:label "other"@de , "andere"@en ;
 rdfs:subClassOf <http://purl.org/coscine/vocabularies/facs/instruments>
 .