diff --git a/src/util/rand.scad b/src/util/rand.scad
index e8430c57..52def6f9 100644
--- a/src/util/rand.scad
+++ b/src/util/rand.scad
@@ -1,2 +1,12 @@
+/**
+* reverse.scad
+*
+* @copyright Justin Lin, 2019
+* @license https://opensource.org/licenses/lgpl-3.0.html
+*
+* @see https://openhome.cc/eGossip/OpenSCAD/lib2-rand.html
+*
+**/ 
+
 function rand(min_value = 0, max_value = 1, seed_value) = 
     is_undef(seed_value) ? rands(min_value, max_value , 1)[0] : rands(min_value, max_value , 1, seed_value)[0];
\ No newline at end of file