Fixed broken link

Froussios · Froussios · commit 2ed7cbf679b3 · 2015-05-09T16:12:09.000+02:00
diff --git a/Part 4 - Concurrency/3. Sequences of coincidence.md b/Part 4 - Concurrency/3. Sequences of coincidence.md
@@ -293,4 +293,4 @@ You can also implement `groupJoin` with `join` and `groupBy`. Doing so would req
 
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-| [Testing Rx](/Part 4 - Concurrency/2. Testing Rx.md) | [Backpressure](/Part 4 - Concurrency/4. Backpressure) |
+| [Testing Rx](/Part 4 - Concurrency/2. Testing Rx.md) | [Backpressure](/Part 4 - Concurrency/4. Backpressure.md) |
