--- a/src/main/java/org/sbaresearch/owl/OwlApiFacade.java
+++ b/src/main/java/org/sbaresearch/owl/OwlApiFacade.java
@@ -23,6 +23,7 @@
 import com.hp.hpl.jena.ontology.OntModelSpec;
 import com.hp.hpl.jena.rdf.model.Model;
 import com.hp.hpl.jena.rdf.model.ModelFactory;
+import net.sf.oval.constraint.NotNull;
 import net.sf.oval.guard.Guarded;
 import net.sf.oval.guard.Pre;
 import org.semanticweb.owlapi.apibinding.OWLManager;
@@ -462,4 +463,12 @@
         return getClassesOfIndividual(individual).contains(classIRI);
     }
 
+    public static String toXMLString(@NotNull OWLOntology ontology) throws OWLOntologyStorageException, IOException {
+        ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
+        ontology.getOWLOntologyManager().saveOntology(ontology, new RDFXMLOntologyFormat(), outputStream);
+        String result = outputStream.toString();
+        outputStream.close();
+        return result;
+    }
+
 }