diff --git a/nnsum/data/summarization_dataset.py b/nnsum/data/summarization_dataset.py
index ec2c145..7dfd854 100644
--- a/nnsum/data/summarization_dataset.py
+++ b/nnsum/data/summarization_dataset.py
@@ -47,7 +47,7 @@ def _collect_references(self, references_dir):
 
         ref_paths = defaultdict(list)
         for path in references_dir.glob("*"):
-            ref_id = path.stem.rsplit(".")[0]
+            ref_id = path.stem.rsplit(".", 1)[0]
             ref_paths[ref_id].append(path)
 
         all_ref_paths = []