diff --git a/doc/sphinx/cython/thermo.rst b/doc/sphinx/cython/thermo.rst
index ac8c74ba1..98c51eb70 100644
--- a/doc/sphinx/cython/thermo.rst
+++ b/doc/sphinx/cython/thermo.rst
@@ -8,3 +8,4 @@ These classes are used to describe the thermodynamic state of a system.
 .. autoclass:: ThermoPhase(infile='', phaseid='')
 .. autoclass:: InterfacePhase(infile='', phaseid='')
 .. autoclass:: PureFluid(infile='', phaseid='')
+.. autoclass:: Mixture