diff --git a/docs/features.rst b/docs/features.rst
index c4cd09e53..a173e0b57 100644
--- a/docs/features.rst
+++ b/docs/features.rst
@@ -133,4 +133,5 @@ Also, by default, we turn off dithering for deterministic feature extraction.
 .. _lilcom: https://github.com/danpovey/lilcom
 .. _power quantity: https://en.wikipedia.org/wiki/Power,_root-power,_and_field_quantities
 .. _Torchaudio CMVN: https://pytorch.org/audio/stable/transforms.html#slidingwindowcmn
-.. _kaldifeat: https://github.com/csukuangfj/kaldifeat
\ No newline at end of file
+.. _kaldifeat: https://github.com/csukuangfj/kaldifeat
+.. _opensmile: https://github.com/audeering/opensmile