Fixing the link to Time, Clocks, and the Ordering of Events in a

Distributed System in concurrency README.md

concurrency/README.md

@@ -2,7 +2,7 @@
 
 * [Everything You Always Wanted to Know About Synchronization but Were Afraid to Ask](http://sigops.org/sosp/sosp13/papers/p33-david.pdf)
 
-* [Time, Clocks, and the Ordering of Events in a Distributed System](http://research.microsoft.com/en-us/um/people/lamport/pubs/time-clocks.pdf)
+* [Time, Clocks, and the Ordering of Events in a Distributed System](http://lamport.azurewebsites.net/pubs/time-clocks.pdf)
 
 * [Heap Architectures For Concurrent Languages Using Message Passing](http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.108.1302&rep=rep1&type=pdf)