diff --git a/extract-fields.ini b/extract-fields.ini
index 90c9569..f97d5ee 100644
--- a/extract-fields.ini
+++ b/extract-fields.ini
@@ -18,6 +18,9 @@
 path = uri
 value = get("UID")
 
+path = doi
+value = get("dynamic_data.cluster_related.identifiers.identifier").filter(i => i.type === "doi").map("value").uniq()
+
 path = title
 value = get('static_data.summary.titles.title').filter(title => title.type === "item").map(title => title.content).join('|')