diff --git a/dhp-workflows/dhp-graph-provision/src/main/resources/eu/dnetlib/dhp/sx/provision/scholix_index.json b/dhp-workflows/dhp-graph-provision/src/main/resources/eu/dnetlib/dhp/sx/provision/scholix_index.json
index 93032712a..86e80206f 100644
--- a/dhp-workflows/dhp-graph-provision/src/main/resources/eu/dnetlib/dhp/sx/provision/scholix_index.json
+++ b/dhp-workflows/dhp-graph-provision/src/main/resources/eu/dnetlib/dhp/sx/provision/scholix_index.json
@@ -41,7 +41,8 @@
         }
       },
       "publicationDate": {
-        "type": "keyword"
+        "type":   "date",
+        "format": "yyyy-MM-dd"
       },
       "relationship": {
         "properties": {