diff --git a/docs/conf.py b/docs/conf.py
index a8cf752fb..5d75eb094 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -148,5 +148,5 @@
   r'https://doi.org/20.500.12738/6561',  # 08.01.2023: does not resolve anymore
   r'https://doi.org/10.1021/ie4033999',  # 28.02.2023: does not resolve anymore for some reason
   r'https://doi.org/10.1002/bbpc.19900940121',  # 13.03.2023 ...?
-  r' http://www.coolprop.org/fluid_properties/Incompressibles.html',  # 02.12.2023 ...?
+  r'http://www.coolprop.org/fluid_properties/Incompressibles.html',  # 02.12.2023 ...?
 ]