diff --git a/src/main/java/org/gcube/portlets/user/geoportaldataviewer/client/LayerManager.java b/src/main/java/org/gcube/portlets/user/geoportaldataviewer/client/LayerManager.java
index 3f35d3e..458fa56 100644
--- a/src/main/java/org/gcube/portlets/user/geoportaldataviewer/client/LayerManager.java
+++ b/src/main/java/org/gcube/portlets/user/geoportaldataviewer/client/LayerManager.java
@@ -94,6 +94,9 @@ import ol.geom.Geometry;
  */
 public class LayerManager {
 
+	private static final String ZOOM_TO_LAYERS_LABEL = "Zoom...";
+	private static final String ZOOM_TO_LAYERS_TITLE = "Zoom to Layers";
+
 	/** The ol map. */
 	private OpenLayerMap olMap;
 
@@ -1010,9 +1013,9 @@ public class LayerManager {
 			}
 		});
 
-		final Button buttonViewLayers = new Button("Zoom in...");
+		final Button buttonViewLayers = new Button(ZOOM_TO_LAYERS_LABEL);
 		buttonViewLayers.getElement().setId("go-to-layers");
-		buttonViewLayers.getElement().setTitle("Zoom in...");
+		buttonViewLayers.getElement().setTitle(ZOOM_TO_LAYERS_TITLE);
 		buttonViewLayers.setType(ButtonType.LINK);
 
 		if (olMap.getCurrentZoomLevel() >= OLMapManager.LAYER_DETAIL_MAX_RESOLUTION) {
@@ -1202,9 +1205,9 @@ public class LayerManager {
 			}
 		});
 
-		final Button buttonViewLayers = new Button("Zoom in...");
+		final Button buttonViewLayers = new Button(ZOOM_TO_LAYERS_LABEL);
 		buttonViewLayers.getElement().setId("go-to-layers");
-		buttonViewLayers.getElement().setTitle("Zoom in...");
+		buttonViewLayers.getElement().setTitle(ZOOM_TO_LAYERS_TITLE);
 		buttonViewLayers.setType(ButtonType.LINK);
 
 		if (olMap.getCurrentZoomLevel() >= OLMapManager.LAYER_DETAIL_MAX_RESOLUTION) {