diff --git a/dashboard/src/app/sortby.pipe.ts b/dashboard/src/app/sortby.pipe.ts
index 653ae7d..12c498f 100644
--- a/dashboard/src/app/sortby.pipe.ts
+++ b/dashboard/src/app/sortby.pipe.ts
@@ -1,3 +1,5 @@
+// Thank to http://4dev.tech/2016/09/angular2-how-to-sort-a-json-dataset-by-field/
+
 import { Pipe, PipeTransform } from '@angular/core';
 
 @Pipe({name: "sortBy"})