Update index.html

index.html

@@ -90,7 +90,7 @@ var _hmt = _hmt || [];
             <h1>PaddlePaddle</h1>
             <hr>
 	    <p>Open and Easy-to-Use Deep Learning Platform for Enterprise and Research</p>
-	    <a href="http://book.paddlepaddle.org" class="btn btn-primary btn-xl page-scroll btn-pd">Deep Learning 101</a>
+	    <a href="http://book.paddlepaddle.org/index.en.html" class="btn btn-primary btn-xl page-scroll btn-pd">Deep Learning 101</a>
 	    <a href="http://paddlepaddle.org/doc/" class="btn btn-primary btn-xl page-scroll btn-pd">Documentation</a>
 	    <a href="https://github.com/baidu/paddle" class="btn btn-primary btn-xl page-scroll btn-pd">Code</a>
         </div>