fixed broken link

Author: brunjlar

README.markdown

@@ -27,7 +27,7 @@ In order to provide a powerful and flexible API, models are constructed using *c
 [Arrow and ArrowChoice](https://hackage.haskell.org/package/base-4.9.0.0/docs/Control-Arrow.html) typeclasses. 
 They can therefore easily be combined and transformed.
 
-Once a model has been constructed, it can be hooked up into a customized training algorithm using [pipes](https://hackage.haskell.org/package/pipes pipes),
+Once a model has been constructed, it can be hooked up into a customized training algorithm using [pipes](https://hackage.haskell.org/package/pipes),
 so that various aspects of the algorithm (loading data, choosing random samples, reporting intermediate results, stop criterium etc.) can be defined in a modular,
 decoupled way.