Update free-books.md

ericdouglas · web-flow · commit 62cb5c42ce5b · 2017-03-28T07:18:42.000-03:00
diff --git a/extras/free-books.md b/extras/free-books.md
@@ -79,6 +79,7 @@ Name | Author(s)
 ### Computer Architecture
 
 ### Operating Systems
+Name | Author(s)
 :-- | :--: 
 [Operating Systems: Three Easy Pieces](http://pages.cs.wisc.edu/~remzi/OSTEP/) |Remzi H. Arpaci-Dusseau, Andrea C. Arpaci-Dusseau
 
