diff --git a/src/fr/inrialpes/exmo/align/onto/Ontology.java b/src/fr/inrialpes/exmo/align/onto/Ontology.java
index e5197635d18882d9a6ec374bd71b9bdf0ef68e34..397c362a68d864543041aa3891177b4fa3c559cb 100644
--- a/src/fr/inrialpes/exmo/align/onto/Ontology.java
+++ b/src/fr/inrialpes/exmo/align/onto/Ontology.java
@@ -22,7 +22,9 @@ package fr.inrialpes.exmo.align.onto;
 
 import java.net.URI;
 
-public interface Ontology<O> {
+import org.semanticweb.owl.align.Visitable;
+
+public interface Ontology<O> extends Visitable {
 
     public URI getURI();
     public URI getFile();