diff --git a/ProjectClock/StopwatchViewController.swift b/ProjectClock/StopwatchViewController.swift
index a013ed7..cfe64ec 100644
--- a/ProjectClock/StopwatchViewController.swift
+++ b/ProjectClock/StopwatchViewController.swift
@@ -3,7 +3,7 @@
 //  ProjectClock
 //
 //  Created by Dallon Archibald on 1/23/21.
-//
+//  Reference: https://youtu.be/H691qFRpaWA
 
 import UIKit