diff --git a/doc/09_voronoi.md b/doc/09_voronoi.md
index c3ec501..1a19103 100644
--- a/doc/09_voronoi.md
+++ b/doc/09_voronoi.md
@@ -27,9 +27,12 @@ PostGIS wil include this in future versions ([doc for dev branch](http://postgis
 ```sql
 WITH a AS (
     SELECT
-    ARRAY[ST_GeomFromText('POINT(2.1744 41.403)'),ST_GeomFromText('POINT(2.1228 41.380)'),ST_GeomFromText('POINT(2.1511 41.374)'),ST_GeomFromText('POINT(2.1528 41.413)'),ST_GeomFromText('POINT(2.165 41.391)'),ST_GeomFromText('POINT(2.1498 41.371)'),ST_GeomFromText('POINT(2.1533 41.368)'),ST_GeomFromText('POINT(2.131386 41.41399)')] AS geomin
+    ARRAY[ST_GeomFromText('POINT(2.1744 41.403)', 4326),ST_GeomFromText('POINT(2.1228 41.380)', 4326),ST_GeomFromText('POINT(2.1511 41.374)', 4326),ST_GeomFromText('POINT(2.1528 41.413)', 4326),ST_GeomFromText('POINT(2.165 41.391)', 4326),ST_GeomFromText('POINT(2.1498 41.371)', 4326),ST_GeomFromText('POINT(2.1533 41.368)', 4326),ST_GeomFromText('POINT(2.131386 41.41399)', 4326)] AS geomin
 )
 SELECT
-    CDB_voronoi(geomin, 0.2, 1e-9) as result
+    st_transform(
+    (st_dump(CDB_voronoi(geomin, 0.2, 1e-9)
+    )).geom
+        , 3857) as the_geom_webmercator
 FROM a;
 ```