diff --git a/_includes/notes_graph.html b/_includes/notes_graph.html
index 7dbf3e6..e4a2e49 100644
--- a/_includes/notes_graph.html
+++ b/_includes/notes_graph.html
@@ -151,7 +151,7 @@
       }
 
       for (const edge of next) {
-        if (!set.has(`${edge.source}-${edge.target}`)) {
+        if (!set.has(`${edge.source.id}-${edge.target.id}`)) {
           return false;
         }
       }