diff --git a/Sorts/PigeonHoleSort.js b/Sorts/PigeonHoleSort.js
index 8af87c882..b5871ed35 100644
--- a/Sorts/PigeonHoleSort.js
+++ b/Sorts/PigeonHoleSort.js
@@ -1,4 +1,6 @@
 /*
+https://en.wikipedia.org/wiki/Pigeonhole_sort
+
 *Pigeonhole sorting is a sorting algorithm that is suitable
 * for sorting lists of elements where the number of elements
 * (n) and the length of the range of possible key values (N)