diff --git a/src/mlpack/methods/reinforcement_learning/environment/continuous_double_pole_cart.hpp b/src/mlpack/methods/reinforcement_learning/environment/continuous_double_pole_cart.hpp
index 777734e219..046e6a2619 100644
--- a/src/mlpack/methods/reinforcement_learning/environment/continuous_double_pole_cart.hpp
+++ b/src/mlpack/methods/reinforcement_learning/environment/continuous_double_pole_cart.hpp
@@ -183,7 +183,7 @@ class ContinuousDoublePoleCart
 
   /**
    * This is the ordinary differential equations required for estimation of
-   * nextState through RK4 method.
+   * next state through RK4 method.
    *
    * @param state The current state.
    * @param action The action taken.
diff --git a/src/mlpack/methods/reinforcement_learning/environment/double_pole_cart.hpp b/src/mlpack/methods/reinforcement_learning/environment/double_pole_cart.hpp
index c5a8e810aa..4909daa91f 100755
--- a/src/mlpack/methods/reinforcement_learning/environment/double_pole_cart.hpp
+++ b/src/mlpack/methods/reinforcement_learning/environment/double_pole_cart.hpp
@@ -183,7 +183,7 @@ class DoublePoleCart
 
   /**
    * This is the ordinary differential equations required for estimation of
-   * nextState through RK4 method.
+   * next state through RK4 method.
    *
    * @param state The current state.
    * @param action The action taken.