diff --git a/ThreeCSG.js b/ThreeCSG.js
index d34304f..54297f0 100644
--- a/ThreeCSG.js
+++ b/ThreeCSG.js
@@ -75,7 +75,7 @@ THREE.CSG = {
 			// Vertices
 			vertices = [];
 			for ( j = 0; j < polygons[i].vertices.length; j++ ) {
-				vertices.push( this.getGeometryVertice( three_geometry, polygons[i].vertices[j].pos ) );
+				vertices.push( THREE.CSG.getGeometryVertice( three_geometry, polygons[i].vertices[j].pos ) );
 			}
 			if ( vertices[0] === vertices[vertices.length - 1] ) {
 				vertices.pop( );
@@ -105,4 +105,4 @@ THREE.CSG = {
 		geometry.vertices.push( new THREE.Vector3( vertice_position.x, vertice_position.y, vertice_position.z ) );
 		return geometry.vertices.length - 1;
 	}
-};
\ No newline at end of file
+};