Merge pull request Froussios#56 from ihac/patch-1

Typo fix in Part 3 Chapter 5

Author: Froussios

Part 3 - Taming the sequence/5. Time-shifted sequences.md

@@ -81,7 +81,7 @@ We see a lot of empty lists here. This is because the buffer is emitted both whe
 
 #### buffer with signal
 
-Instead of fixed points in time, you can also signal `buffer` with an observable to flush. Every time the signal emits onNext, the values in the buffer will be emitted will be emitted. Buffering with a signal can be very useful if you want to buffer values until the moment that you are ready for them.
+Instead of fixed points in time, you can also signal `buffer` with an observable to flush. Every time the signal emits onNext, the values in the buffer will be emitted. Buffering with a signal can be very useful if you want to buffer values until the moment that you are ready for them.
 
 ![](https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/buffer8.png)
 
@@ -155,7 +155,7 @@ Observable.interval(100, TimeUnit.MILLISECONDS).take(10)
 
 #### buffer by signal
 
-The last and most powerful variant or `buffer` allows you to define the start and the end of buffers using signaling observables.
+The last and most powerful variant of `buffer` allows you to define the start and the end of buffers using signaling observables.
 ```java
 public final <TOpening,TClosing> Observable<java.util.List<T>> buffer(
 	Observable<? extends TOpening> bufferOpenings,