diff --git a/src/main/java/org/apache/commons/graph/flow/FlowNetworkHandler.java b/src/main/java/org/apache/commons/graph/flow/FlowNetworkHandler.java
index 64e55d5..c116714 100644
--- a/src/main/java/org/apache/commons/graph/flow/FlowNetworkHandler.java
+++ b/src/main/java/org/apache/commons/graph/flow/FlowNetworkHandler.java
@@ -42,7 +42,7 @@
  * @param <V> the vertex type
  * @param <W> the weight type
  */
-class FlowNetworkHandler<V, E, W>
+final class FlowNetworkHandler<V, E, W>
     extends BaseGraphVisitHandler<V, E, DirectedGraph<V, E>, W>
 {
 
diff --git a/src/main/java/org/apache/commons/graph/spanning/SuperVertex.java b/src/main/java/org/apache/commons/graph/spanning/SuperVertex.java
index 84f4a03..78f5731 100644
--- a/src/main/java/org/apache/commons/graph/spanning/SuperVertex.java
+++ b/src/main/java/org/apache/commons/graph/spanning/SuperVertex.java
@@ -37,7 +37,7 @@
  * @param <G>  the input Graph type
  * @param <WC> the weight operations
  */
-class SuperVertex<V, W, WE>
+final class SuperVertex<V, W, WE>
     implements Iterable<V>
 {