diff --git a/docs/source/util.rst b/docs/source/util.rst
index ad6f429..02495f4 100644
--- a/docs/source/util.rst
+++ b/docs/source/util.rst
@@ -23,6 +23,7 @@ Functions:
 #. :c:func:`glm_max`
 #. :c:func:`glm_clamp`
 #. :c:func:`glm_lerp`
+#. :c:func:`glm_swapf`
 
 Functions documentation
 ~~~~~~~~~~~~~~~~~~~~~~~