diff --git a/examples/structured_2d_dgsem/elixir_euler_vortex_perk4.jl b/examples/structured_2d_dgsem/elixir_euler_vortex_perk4.jl
index 0f918bed16c..ce4f0aceacf 100644
--- a/examples/structured_2d_dgsem/elixir_euler_vortex_perk4.jl
+++ b/examples/structured_2d_dgsem/elixir_euler_vortex_perk4.jl
@@ -1,5 +1,5 @@
 
-using OrdinaryDiffEq # Requiref for `CallbackSet`
+using OrdinaryDiffEq # Required for `CallbackSet`
 using Trixi
 
 # Ratio of specific heats
diff --git a/examples/tree_1d_dgsem/elixir_hypdiff_nonperiodic_perk4.jl b/examples/tree_1d_dgsem/elixir_hypdiff_nonperiodic_perk4.jl
index 2bbf930932c..b43ab3c416d 100644
--- a/examples/tree_1d_dgsem/elixir_hypdiff_nonperiodic_perk4.jl
+++ b/examples/tree_1d_dgsem/elixir_hypdiff_nonperiodic_perk4.jl
@@ -1,5 +1,5 @@
 
-using OrdinaryDiffEq
+using OrdinaryDiffEq # Required for `CallbackSet`
 using Trixi
 
 # Convex and ECOS are imported because they are used for finding the optimal time step and optimal