diff --git a/docs/033/index.ipynb b/docs/033/index.ipynb
index ca8efbd..a67324b 100644
--- a/docs/033/index.ipynb
+++ b/docs/033/index.ipynb
@@ -1224,7 +1224,7 @@
    "metadata": {},
    "source": [
     ":::{seealso}\n",
-    "- [Section of helicity formalism in **TR-015** (Spin alignment implementation)](https://compwa.github.io/report/015.html#helicity-formalism)\n",
+    "- [Section of helicity formalism in **TR-015** (Spin alignment implementation)](../015/index.ipynb#helicity-formalism)\n",
     "- [Helicity versus canonical in Ampform](https://ampform.readthedocs.io/stable/usage/helicity/formalism.html)\n",
     ":::"
    ]