Update index.md

Author: dsyme

history/index.md

@@ -8,3 +8,6 @@ headline: History
 
 * [Matching slides](https://github.com/dsyme/fsharp-presentations/tree/master/2021-06-21-hopl)
 
+* [Matching talk: Narratives from The Early History of F#](https://www.pldi21.org/prerecorded_hopl.19.html)
+
+* [Matching talk #2: Narratives and Lessons from The Early History of F#](https://www.youtube.com/watch?v=ynIe8Q7kMSg)