--- a/docs/mappings/index-settings.json	Wed Nov 14 17:48:03 2018 +0100
+++ b/docs/mappings/index-settings.json	Fri Nov 16 15:42:06 2018 +0100
@@ -79,6 +79,9 @@
 				"internal_id": {
 					"type": "keyword"
 				},
+				"reference_id": {
+					"type": "keyword"
+				},
 				"content_type": {
 					"type": "keyword"
 				},