Fix typo in step 67

diff --git a/examples/step-67/doc/results.dox b/examples/step-67/doc/results.dox
index b94fc295247ea6a7b84b419ea6525c75653ac76c..8e599d249ea381b14af9f6eaed526a678d6cf54d 100644 (file)
--- a/examples/step-67/doc/results.dox
+++ b/examples/step-67/doc/results.dox
@@ -795,7 +795,7 @@ matched layers</a> -- where the solution is damped without reflection
 -- are common.
 
 
-<h4>Extension to the compressible Navier-Stokes equation</h4>
+<h4>Extension to the compressible Navier-Stokes equations</h4>
 
 The solver presented in this tutorial program can also be extended to the
 compressible Navier--Stokes equations by adding viscous terms, as described in