diff --git a/sources/diagramview.cpp b/sources/diagramview.cpp
index b4941f53d..268b3f190 100644
--- a/sources/diagramview.cpp
+++ b/sources/diagramview.cpp
@@ -1327,7 +1327,7 @@ DiagramImageItem *DiagramView::addDiagramImageAtPos(const QPointF &pos) {
 	@param pos Position du champ de texte ajoute
 	@return le champ de texte ajoute
 */
-IndependentTextItem *DiagramView::addDiagramTextAtPos(const QPointF &pos, const QString text) {
+IndependentTextItem *DiagramView::addDiagramTextAtPos(const QPointF &pos, const QString &text) {
 	if (!isInteractive() || scene -> isReadOnly()) return(0);
 	
 	// cree un nouveau champ de texte
diff --git a/sources/diagramview.h b/sources/diagramview.h
index ab3465a18..cd532d643 100644
--- a/sources/diagramview.h
+++ b/sources/diagramview.h
@@ -76,7 +76,7 @@ class DiagramView : public QGraphicsView {
 	void editText();
 	void addImage();
 	void editImage();
-	IndependentTextItem *addDiagramTextAtPos(const QPointF &, const QString text = 0);
+	IndependentTextItem *addDiagramTextAtPos(const QPointF &, const QString &text = 0);
 	DiagramImageItem *addDiagramImageAtPos(const QPointF &);
 	
 	protected: