diff --git a/src/main/java/eu/dnetlib/app/directindex/mapping/SolrRecordMapper.java b/src/main/java/eu/dnetlib/app/directindex/mapping/SolrRecordMapper.java
index 87e4daf..bab5ca3 100644
--- a/src/main/java/eu/dnetlib/app/directindex/mapping/SolrRecordMapper.java
+++ b/src/main/java/eu/dnetlib/app/directindex/mapping/SolrRecordMapper.java
@@ -266,6 +266,7 @@ public class SolrRecordMapper {
 
 		final Instance instance = new Instance();
 
+		// TODO verificare il valore (dovrebbe essere classid="0004" classname="Conference object")
 		instance.setInstancetype(re.getResourceType());
 		instance.setCollectedfrom(collectedFrom);
 		instance.setHostedby(hostedBy);
diff --git a/src/main/java/eu/dnetlib/app/directindex/solr/XMLSolrSerializer.java b/src/main/java/eu/dnetlib/app/directindex/solr/XMLSolrSerializer.java
index 0b2e64f..da9ff01 100644
--- a/src/main/java/eu/dnetlib/app/directindex/solr/XMLSolrSerializer.java
+++ b/src/main/java/eu/dnetlib/app/directindex/solr/XMLSolrSerializer.java
@@ -132,27 +132,26 @@ public class XMLSolrSerializer {
 		}
 	}
 
-	private static void addResultInstance(final Element childrenNode, final Instance p) {
-		// TODO Auto-generated method stub
-		/*
+	private static void addResultInstance(final Element childrenNode, final Instance i) {
+		final Element instanceNode = childrenNode.addElement("instance");
 
+		//TODO manca il code o il name
+		addStructuredField(instanceNode, "instancetype", i.getInstancetype(), ModelConstants.DNET_PUBLICATION_RESOURCE, null);
 
+		addStructuredField(instanceNode, "accessright", i.getAccessright().getCode(), i.getAccessright().getLabel(), ModelConstants.DNET_ACCESS_MODES, null);
+
+		final Element collectedFrom = instanceNode.addElement("collectedfrom");
+		collectedFrom.addAttribute("id", i.getCollectedfrom().getDsId());
+		collectedFrom.addAttribute("name", i.getCollectedfrom().getDsName());
+
+		final Element hostedBy = instanceNode.addElement("hostedby");
+		hostedBy.addAttribute("id", i.getHostedby().getDsId());
+		hostedBy.addAttribute("name", i.getHostedby().getDsName());
+
+		if (i.getUrl() != null) {
+			i.getUrl().forEach(url -> instanceNode.addElement("webresource").addElement("url").addText(url));
+		}
 
-	<children>
-		<instance>
-			<accessright classid="CLOSED" classname="Closed Access" schemeid="dnet:access_modes" schemename="dnet:access_modes" />
-			<collectedfrom name="Croatian Scientific Bibliography - CROSBI" id="openaire____::345c9d171ef3c5d706d08041d506428c" />
-			<hostedby name="Croatian Scientific Bibliography - CROSBI" id="openaire____::345c9d171ef3c5d706d08041d506428c" />
-			<dateofacceptance>2013-01-01</dateofacceptance>
-			<instancetype classid="0004" classname="Conference object" schemeid="dnet:publication_resource" schemename="dnet:publication_resource" />
-			<refereed classid="0002" classname="nonPeerReviewed" schemeid="dnet:review_levels" schemename="dnet:review_levels" />
-			<webresource>
-				<url>https://www.bib.irb.hr/683750</url>
-			</webresource>
-		</instance>
-	</children>
-</result>
-		 */
 	}
 
 	private static void addRelProject(final Element relsNode, final RelatedRecord p) {