diff --git a/routes/post.py b/routes/post.py
index 420e60e..9918e69 100644
--- a/routes/post.py
+++ b/routes/post.py
@@ -71,7 +71,7 @@ def create_paper(db):
     if "doi" in data:
         paper = create_by_doi(data["doi"], db)
     elif "arxiv_id" in data:
-        paper = create_by_arxiv(data["arxiv"], db)
+        paper = create_by_arxiv(data["arxiv_id"], db)
 
     if paper is None:
         return bottle.HTTPError(409, "Conflict")