diff --git a/Additional-Learning-Resources.md b/Additional-Learning-Resources.md
index eef6162..b0aef1c 100644
--- a/Additional-Learning-Resources.md
+++ b/Additional-Learning-Resources.md
@@ -11,9 +11,7 @@ You can read more about PDF.js here:
 ## Presentations
 
 Videos:
-+ Julian Viereck – Zurich GTUG 2011, http://blog.mozilla.org/labs/2011/10/video-what-is-pdf-js/
-+ Andreas Gal – JSConf.eu, 2011, http://blip.tv/jsconfeu/andreas-gal-pdf-js-5723942
-+ Brendan Dahl - FOSDEM 2013, https://air.mozilla.org/pdfjs-firefoxs-html5-pdf-viewer/
++ Julian Viereck – Zurich GTUG 2011, https://blog.mozilla.org/labs/2011/10/video-what-is-pdf-js/
 + Brendan Dahl - HTML5DevConf 2013, https://www.youtube.com/watch?v=4yLzRoErOHw
 + Mack Duan - Optimizing PDF.js, Mozilla, 2013, https://air.mozilla.org/intern-pdfjs/