diff --git a/pybamm/citations.py b/pybamm/citations.py
index 3451b24947..6f3e366b85 100644
--- a/pybamm/citations.py
+++ b/pybamm/citations.py
@@ -60,8 +60,8 @@ def read_citations(self):
                     citation = ""
                     start = True
 
-        # add the final citation
-        self._all_citations[key] = citation
+            # add the final citation
+            self._all_citations[key] = citation
 
     def register(self, key):
         """Register a paper to be cited. The intended use is that :meth:`register`