diff --git a/advanced/agentmotion/src/main/java/org/arakhne/afc/agentmotion/AligningMotionAlgorithm.java b/advanced/agentmotion/src/main/java/org/arakhne/afc/agentmotion/AligningMotionAlgorithm.java
index e25e7b9d1..7d603a172 100644
--- a/advanced/agentmotion/src/main/java/org/arakhne/afc/agentmotion/AligningMotionAlgorithm.java
+++ b/advanced/agentmotion/src/main/java/org/arakhne/afc/agentmotion/AligningMotionAlgorithm.java
@@ -32,6 +32,7 @@
  * @mavenartifactid $ArtifactId$
  * @since 14.0
  */
+@FunctionalInterface
 public interface AligningMotionAlgorithm {
 
 	/** Calculate the rotation for being aligned to the target vector.
diff --git a/advanced/agentmotion/src/main/java/org/arakhne/afc/agentmotion/ArrivingMotionAlgorithm.java b/advanced/agentmotion/src/main/java/org/arakhne/afc/agentmotion/ArrivingMotionAlgorithm.java
index 7a581224f..0bcc00f58 100644
--- a/advanced/agentmotion/src/main/java/org/arakhne/afc/agentmotion/ArrivingMotionAlgorithm.java
+++ b/advanced/agentmotion/src/main/java/org/arakhne/afc/agentmotion/ArrivingMotionAlgorithm.java
@@ -33,6 +33,7 @@
  * @mavenartifactid $ArtifactId$
  * @since 14.0
  */
+@FunctionalInterface
 public interface ArrivingMotionAlgorithm {
 
 	/** Calculate the linear motion for arriving the target point.
diff --git a/advanced/agentmotion/src/main/java/org/arakhne/afc/agentmotion/FacingMotionAlgorithm.java b/advanced/agentmotion/src/main/java/org/arakhne/afc/agentmotion/FacingMotionAlgorithm.java
index 7ef58c619..d93709367 100644
--- a/advanced/agentmotion/src/main/java/org/arakhne/afc/agentmotion/FacingMotionAlgorithm.java
+++ b/advanced/agentmotion/src/main/java/org/arakhne/afc/agentmotion/FacingMotionAlgorithm.java
@@ -33,6 +33,7 @@
  * @mavenartifactid $ArtifactId$
  * @since 14.0
  */
+@FunctionalInterface
 public interface FacingMotionAlgorithm {
 
 	/** Calculate the rotation for facing the target point.
diff --git a/core/math/src/main/java/org/arakhne/afc/math/geometry/d2/d/ShapeGeometryChangeListener.java b/core/math/src/main/java/org/arakhne/afc/math/geometry/d2/d/ShapeGeometryChangeListener.java
index c1f3d032c..72138fce5 100644
--- a/core/math/src/main/java/org/arakhne/afc/math/geometry/d2/d/ShapeGeometryChangeListener.java
+++ b/core/math/src/main/java/org/arakhne/afc/math/geometry/d2/d/ShapeGeometryChangeListener.java
@@ -30,6 +30,7 @@
  * @mavenartifactid $ArtifactId$
  * @since 13.0
  */
+@FunctionalInterface
 public interface ShapeGeometryChangeListener extends EventListener {
 
 	/** Invoked when the given shape has change of geometry.
diff --git a/core/math/src/main/java/org/arakhne/afc/math/geometry/d2/i/ShapeGeometryChangeListener.java b/core/math/src/main/java/org/arakhne/afc/math/geometry/d2/i/ShapeGeometryChangeListener.java
index 0ee5f4ae7..0b4784aa4 100644
--- a/core/math/src/main/java/org/arakhne/afc/math/geometry/d2/i/ShapeGeometryChangeListener.java
+++ b/core/math/src/main/java/org/arakhne/afc/math/geometry/d2/i/ShapeGeometryChangeListener.java
@@ -30,6 +30,7 @@
  * @mavenartifactid $ArtifactId$
  * @since 13.0
  */
+@FunctionalInterface
 public interface ShapeGeometryChangeListener extends EventListener {
 
 	/** Invoked when the given shape has change of geometry.
diff --git a/core/math/src/main/java/org/arakhne/afc/math/graph/astar/AStarHeuristic.java b/core/math/src/main/java/org/arakhne/afc/math/graph/astar/AStarHeuristic.java
index 6acd5dabc..01937d1e6 100644
--- a/core/math/src/main/java/org/arakhne/afc/math/graph/astar/AStarHeuristic.java
+++ b/core/math/src/main/java/org/arakhne/afc/math/graph/astar/AStarHeuristic.java
@@ -35,6 +35,7 @@
  * @since 13.0
  * @see AStar
  */
+@FunctionalInterface
 public interface AStarHeuristic<PT extends GraphPoint<PT, ?>> {
 
 	/** Evaluate the distance between two points in the graph.
diff --git a/core/math/src/main/java/org/arakhne/afc/math/tree/iterator/BroadFirstIterationListener.java b/core/math/src/main/java/org/arakhne/afc/math/tree/iterator/BroadFirstIterationListener.java
index a22dc3195..5d62c12e6 100644
--- a/core/math/src/main/java/org/arakhne/afc/math/tree/iterator/BroadFirstIterationListener.java
+++ b/core/math/src/main/java/org/arakhne/afc/math/tree/iterator/BroadFirstIterationListener.java
@@ -31,6 +31,7 @@
  * @mavenartifactid $ArtifactId$
  * @since 13.0
  */
+@FunctionalInterface
 public interface BroadFirstIterationListener extends EventListener {
 
 	/** Invoked when a row of tree nodes was completely replied by the iterator.
diff --git a/core/math/src/main/java/org/arakhne/afc/math/tree/iterator/DataSelector.java b/core/math/src/main/java/org/arakhne/afc/math/tree/iterator/DataSelector.java
index 11c67d2bd..540b6afbf 100644
--- a/core/math/src/main/java/org/arakhne/afc/math/tree/iterator/DataSelector.java
+++ b/core/math/src/main/java/org/arakhne/afc/math/tree/iterator/DataSelector.java
@@ -35,6 +35,7 @@
  * @see PostfixDataDepthFirstTreeIterator
  * @see DataBroadFirstTreeIterator
  */
+@FunctionalInterface
 public interface DataSelector<D> {
 
 	/** Replies if the specified data could be replied by the iterator.
diff --git a/core/math/src/main/java/org/arakhne/afc/math/tree/iterator/NodeSelector.java b/core/math/src/main/java/org/arakhne/afc/math/tree/iterator/NodeSelector.java
index 6f8b3a61f..b56dba7b4 100644
--- a/core/math/src/main/java/org/arakhne/afc/math/tree/iterator/NodeSelector.java
+++ b/core/math/src/main/java/org/arakhne/afc/math/tree/iterator/NodeSelector.java
@@ -37,6 +37,7 @@
  * @see PostfixDataDepthFirstTreeIterator
  * @see DataBroadFirstTreeIterator
  */
+@FunctionalInterface
 public interface NodeSelector<N extends TreeNode<?, ?>> {
 
 	/** Replies if the specified node could be treated by the iterator.