diff --git a/src/webgl/p5.Geometry.js b/src/webgl/p5.Geometry.js
index c7cc72cac3..d8b1f2e0b5 100644
--- a/src/webgl/p5.Geometry.js
+++ b/src/webgl/p5.Geometry.js
@@ -6,6 +6,7 @@
  * @requires p5.Geometry
  */
 
+//some of the functions are adjusted from Three.js(http://threejs.org)
 
 import * as constants from '../core/constants';
 import { DataArray } from './p5.DataArray';