diff --git a/dnet-ariadneplus-graphdb-publisher/src/main/resources/eu/dnetlib/ariadneplus/sparql/check_missing_mandatory_coll_fields.sparql b/dnet-ariadneplus-graphdb-publisher/src/main/resources/eu/dnetlib/ariadneplus/sparql/check_missing_mandatory_coll_fields.sparql
index f129690..a906c4d 100644
--- a/dnet-ariadneplus-graphdb-publisher/src/main/resources/eu/dnetlib/ariadneplus/sparql/check_missing_mandatory_coll_fields.sparql
+++ b/dnet-ariadneplus-graphdb-publisher/src/main/resources/eu/dnetlib/ariadneplus/sparql/check_missing_mandatory_coll_fields.sparql
@@ -51,14 +51,14 @@ SELECT * WHERE {
         ?s rdf:type <https://www.ariadne-infrastructure.eu/resource/ao/cat/1.1/AO_Collection> .
         MINUS {
             ?s rdf:type <https://www.ariadne-infrastructure.eu/resource/ao/cat/1.1/AO_Collection> .
-            ?s	aocat:was_issued ?agent .
+            ?s	aocat:was_issued ?issued .
         }
     }
     UNION{
         ?s rdf:type <https://www.ariadne-infrastructure.eu/resource/ao/cat/1.1/AO_Collection> .
         MINUS {
             ?s rdf:type <https://www.ariadne-infrastructure.eu/resource/ao/cat/1.1/AO_Collection> .
-            ?s	aocat:was_modified ?agent .
+            ?s	aocat:was_modified ?modified .
         }
      }
     UNION{