diff --git a/appendix/00/index.php b/appendix/00/index.php
index 041cc63..00f2758 100644
--- a/appendix/00/index.php
+++ b/appendix/00/index.php
@@ -1,25 +1,32 @@
-<?php 
-    $path = "../../";
-    include($path."/header.php");
-    include($path."/src/parsedown/Parsedown.php");
+<?php
 
-    echo '
-    <div class="header"><p><a href="https://thebookofshaders.com/">The Book of Shaders</a> by <a href="http://patriciogonzalezvivo.com">Patricio Gonzalez Vivo</a></p></div>
-    <hr>
-    <div id="content">
-    ';
+	$path = "../..";
+	$README = "README";
+	$language = "";
 
-    $Parsedown = new Parsedown();
-    echo $Parsedown->text(file_get_contents ('README.md'));
+	if ( !empty($_GET['lan']) ) {
+		if (file_exists($README.'-'.$_GET['lan'].'.md')) {
+			$language = '-'.$_GET['lan'];
+			$README .= $language;
+		}
+	}
 
-    echo '
-    </div>
-    <hr>
-    <ul class="navigationBar" >
-        <li class="navigationBar" onclick="previusPage()">&lt; &lt; Previous</li>
-        <li class="navigationBar" onclick="homePage()"> Home </li>
-        <li class="navigationBar" onclick="nextPage()">Next &gt; &gt;</li>
-    </ul>';
+	include($path."/header.php");
+	include($path."/chap-header.php");
+	echo '<div id="content">';
 
-    include($path."/footer.php"); 
+	include($path."/src/parsedown/Parsedown.php");
+	$Parsedown = new Parsedown();
+	echo $Parsedown->text(file_get_contents($README.'.md'));
+
+	echo '
+	</div>
+	<hr>
+	<ul class="navigationBar" >
+		<li class="navigationBar" onclick="previusPage()">&lt; &lt; Previous</li>
+		<li class="navigationBar" onclick="homePage()"> Home </li>
+		<li class="navigationBar" onclick="nextPage()">Next &gt; &gt;</li>
+	</ul>';
+
+	include($path."/footer.php");
 ?>
diff --git a/appendix/01/index.php b/appendix/01/index.php
index 041cc63..00f2758 100644
--- a/appendix/01/index.php
+++ b/appendix/01/index.php
@@ -1,25 +1,32 @@
-<?php 
-    $path = "../../";
-    include($path."/header.php");
-    include($path."/src/parsedown/Parsedown.php");
+<?php
 
-    echo '
-    <div class="header"><p><a href="https://thebookofshaders.com/">The Book of Shaders</a> by <a href="http://patriciogonzalezvivo.com">Patricio Gonzalez Vivo</a></p></div>
-    <hr>
-    <div id="content">
-    ';
+	$path = "../..";
+	$README = "README";
+	$language = "";
 
-    $Parsedown = new Parsedown();
-    echo $Parsedown->text(file_get_contents ('README.md'));
+	if ( !empty($_GET['lan']) ) {
+		if (file_exists($README.'-'.$_GET['lan'].'.md')) {
+			$language = '-'.$_GET['lan'];
+			$README .= $language;
+		}
+	}
 
-    echo '
-    </div>
-    <hr>
-    <ul class="navigationBar" >
-        <li class="navigationBar" onclick="previusPage()">&lt; &lt; Previous</li>
-        <li class="navigationBar" onclick="homePage()"> Home </li>
-        <li class="navigationBar" onclick="nextPage()">Next &gt; &gt;</li>
-    </ul>';
+	include($path."/header.php");
+	include($path."/chap-header.php");
+	echo '<div id="content">';
 
-    include($path."/footer.php"); 
+	include($path."/src/parsedown/Parsedown.php");
+	$Parsedown = new Parsedown();
+	echo $Parsedown->text(file_get_contents($README.'.md'));
+
+	echo '
+	</div>
+	<hr>
+	<ul class="navigationBar" >
+		<li class="navigationBar" onclick="previusPage()">&lt; &lt; Previous</li>
+		<li class="navigationBar" onclick="homePage()"> Home </li>
+		<li class="navigationBar" onclick="nextPage()">Next &gt; &gt;</li>
+	</ul>';
+
+	include($path."/footer.php");
 ?>
diff --git a/appendix/02/index.php b/appendix/02/index.php
index 041cc63..00f2758 100644
--- a/appendix/02/index.php
+++ b/appendix/02/index.php
@@ -1,25 +1,32 @@
-<?php 
-    $path = "../../";
-    include($path."/header.php");
-    include($path."/src/parsedown/Parsedown.php");
+<?php
 
-    echo '
-    <div class="header"><p><a href="https://thebookofshaders.com/">The Book of Shaders</a> by <a href="http://patriciogonzalezvivo.com">Patricio Gonzalez Vivo</a></p></div>
-    <hr>
-    <div id="content">
-    ';
+	$path = "../..";
+	$README = "README";
+	$language = "";
 
-    $Parsedown = new Parsedown();
-    echo $Parsedown->text(file_get_contents ('README.md'));
+	if ( !empty($_GET['lan']) ) {
+		if (file_exists($README.'-'.$_GET['lan'].'.md')) {
+			$language = '-'.$_GET['lan'];
+			$README .= $language;
+		}
+	}
 
-    echo '
-    </div>
-    <hr>
-    <ul class="navigationBar" >
-        <li class="navigationBar" onclick="previusPage()">&lt; &lt; Previous</li>
-        <li class="navigationBar" onclick="homePage()"> Home </li>
-        <li class="navigationBar" onclick="nextPage()">Next &gt; &gt;</li>
-    </ul>';
+	include($path."/header.php");
+	include($path."/chap-header.php");
+	echo '<div id="content">';
 
-    include($path."/footer.php"); 
+	include($path."/src/parsedown/Parsedown.php");
+	$Parsedown = new Parsedown();
+	echo $Parsedown->text(file_get_contents($README.'.md'));
+
+	echo '
+	</div>
+	<hr>
+	<ul class="navigationBar" >
+		<li class="navigationBar" onclick="previusPage()">&lt; &lt; Previous</li>
+		<li class="navigationBar" onclick="homePage()"> Home </li>
+		<li class="navigationBar" onclick="nextPage()">Next &gt; &gt;</li>
+	</ul>';
+
+	include($path."/footer.php");
 ?>
diff --git a/appendix/03/index.php b/appendix/03/index.php
index 041cc63..00f2758 100644
--- a/appendix/03/index.php
+++ b/appendix/03/index.php
@@ -1,25 +1,32 @@
-<?php 
-    $path = "../../";
-    include($path."/header.php");
-    include($path."/src/parsedown/Parsedown.php");
+<?php
 
-    echo '
-    <div class="header"><p><a href="https://thebookofshaders.com/">The Book of Shaders</a> by <a href="http://patriciogonzalezvivo.com">Patricio Gonzalez Vivo</a></p></div>
-    <hr>
-    <div id="content">
-    ';
+	$path = "../..";
+	$README = "README";
+	$language = "";
 
-    $Parsedown = new Parsedown();
-    echo $Parsedown->text(file_get_contents ('README.md'));
+	if ( !empty($_GET['lan']) ) {
+		if (file_exists($README.'-'.$_GET['lan'].'.md')) {
+			$language = '-'.$_GET['lan'];
+			$README .= $language;
+		}
+	}
 
-    echo '
-    </div>
-    <hr>
-    <ul class="navigationBar" >
-        <li class="navigationBar" onclick="previusPage()">&lt; &lt; Previous</li>
-        <li class="navigationBar" onclick="homePage()"> Home </li>
-        <li class="navigationBar" onclick="nextPage()">Next &gt; &gt;</li>
-    </ul>';
+	include($path."/header.php");
+	include($path."/chap-header.php");
+	echo '<div id="content">';
 
-    include($path."/footer.php"); 
+	include($path."/src/parsedown/Parsedown.php");
+	$Parsedown = new Parsedown();
+	echo $Parsedown->text(file_get_contents($README.'.md'));
+
+	echo '
+	</div>
+	<hr>
+	<ul class="navigationBar" >
+		<li class="navigationBar" onclick="previusPage()">&lt; &lt; Previous</li>
+		<li class="navigationBar" onclick="homePage()"> Home </li>
+		<li class="navigationBar" onclick="nextPage()">Next &gt; &gt;</li>
+	</ul>';
+
+	include($path."/footer.php");
 ?>
diff --git a/appendix/04/index.php b/appendix/04/index.php
index 9ab9c01..00f2758 100644
--- a/appendix/04/index.php
+++ b/appendix/04/index.php
@@ -1,31 +1,32 @@
 <?php
 
-    $path = "../../";
-	$subtitle = "learning to fly";
-	$language = isset( $_GET[ 'lan' ] ) ? $_GET[ 'lan' ] : "";
+	$path = "../..";
 	$README = "README";
+	$language = "";
 
-    include($path."/header.php");
-    include($path."/src/parsedown/Parsedown.php");
+	if ( !empty($_GET['lan']) ) {
+		if (file_exists($README.'-'.$_GET['lan'].'.md')) {
+			$language = '-'.$_GET['lan'];
+			$README .= $language;
+		}
+	}
 
-    echo '
-    <div class="header"><p><a href="https://thebookofshaders.com/">The Book of Shaders</a> by <a href="http://patriciogonzalezvivo.com">Patricio Gonzalez Vivo</a></p></div>
-    <hr>
-    <div id="content">
-    ';
+	include($path."/header.php");
+	include($path."/chap-header.php");
+	echo '<div id="content">';
 
-    $Parsedown = new Parsedown();
-    echo $Parsedown->text(file_get_contents ('README.md'));
-    /*
-    echo '
-    </div>
-    <hr>
-    <ul class="navigationBar" >
-        <!--li class="navigationBar" onclick="previusPage()">&lt; &lt; Previous</li /-->
-        <li class="navigationBar" onclick="homePage()"> Home </li>
-        <li class="navigationBar" onclick="nextPage()">Next &gt; &gt;</li>
-    </ul>';
-    //*/
+	include($path."/src/parsedown/Parsedown.php");
+	$Parsedown = new Parsedown();
+	echo $Parsedown->text(file_get_contents($README.'.md'));
 
-    include($path."/footer.php");
+	echo '
+	</div>
+	<hr>
+	<ul class="navigationBar" >
+		<li class="navigationBar" onclick="previusPage()">&lt; &lt; Previous</li>
+		<li class="navigationBar" onclick="homePage()"> Home </li>
+		<li class="navigationBar" onclick="nextPage()">Next &gt; &gt;</li>
+	</ul>';
+
+	include($path."/footer.php");
 ?>
diff --git a/appendix/05/index.php b/appendix/05/index.php
index 041cc63..00f2758 100644
--- a/appendix/05/index.php
+++ b/appendix/05/index.php
@@ -1,25 +1,32 @@
-<?php 
-    $path = "../../";
-    include($path."/header.php");
-    include($path."/src/parsedown/Parsedown.php");
+<?php
 
-    echo '
-    <div class="header"><p><a href="https://thebookofshaders.com/">The Book of Shaders</a> by <a href="http://patriciogonzalezvivo.com">Patricio Gonzalez Vivo</a></p></div>
-    <hr>
-    <div id="content">
-    ';
+	$path = "../..";
+	$README = "README";
+	$language = "";
 
-    $Parsedown = new Parsedown();
-    echo $Parsedown->text(file_get_contents ('README.md'));
+	if ( !empty($_GET['lan']) ) {
+		if (file_exists($README.'-'.$_GET['lan'].'.md')) {
+			$language = '-'.$_GET['lan'];
+			$README .= $language;
+		}
+	}
 
-    echo '
-    </div>
-    <hr>
-    <ul class="navigationBar" >
-        <li class="navigationBar" onclick="previusPage()">&lt; &lt; Previous</li>
-        <li class="navigationBar" onclick="homePage()"> Home </li>
-        <li class="navigationBar" onclick="nextPage()">Next &gt; &gt;</li>
-    </ul>';
+	include($path."/header.php");
+	include($path."/chap-header.php");
+	echo '<div id="content">';
 
-    include($path."/footer.php"); 
+	include($path."/src/parsedown/Parsedown.php");
+	$Parsedown = new Parsedown();
+	echo $Parsedown->text(file_get_contents($README.'.md'));
+
+	echo '
+	</div>
+	<hr>
+	<ul class="navigationBar" >
+		<li class="navigationBar" onclick="previusPage()">&lt; &lt; Previous</li>
+		<li class="navigationBar" onclick="homePage()"> Home </li>
+		<li class="navigationBar" onclick="nextPage()">Next &gt; &gt;</li>
+	</ul>';
+
+	include($path."/footer.php");
 ?>
diff --git a/appendix/06/index.php b/appendix/06/index.php
index 041cc63..00f2758 100644
--- a/appendix/06/index.php
+++ b/appendix/06/index.php
@@ -1,25 +1,32 @@
-<?php 
-    $path = "../../";
-    include($path."/header.php");
-    include($path."/src/parsedown/Parsedown.php");
+<?php
 
-    echo '
-    <div class="header"><p><a href="https://thebookofshaders.com/">The Book of Shaders</a> by <a href="http://patriciogonzalezvivo.com">Patricio Gonzalez Vivo</a></p></div>
-    <hr>
-    <div id="content">
-    ';
+	$path = "../..";
+	$README = "README";
+	$language = "";
 
-    $Parsedown = new Parsedown();
-    echo $Parsedown->text(file_get_contents ('README.md'));
+	if ( !empty($_GET['lan']) ) {
+		if (file_exists($README.'-'.$_GET['lan'].'.md')) {
+			$language = '-'.$_GET['lan'];
+			$README .= $language;
+		}
+	}
 
-    echo '
-    </div>
-    <hr>
-    <ul class="navigationBar" >
-        <li class="navigationBar" onclick="previusPage()">&lt; &lt; Previous</li>
-        <li class="navigationBar" onclick="homePage()"> Home </li>
-        <li class="navigationBar" onclick="nextPage()">Next &gt; &gt;</li>
-    </ul>';
+	include($path."/header.php");
+	include($path."/chap-header.php");
+	echo '<div id="content">';
 
-    include($path."/footer.php"); 
+	include($path."/src/parsedown/Parsedown.php");
+	$Parsedown = new Parsedown();
+	echo $Parsedown->text(file_get_contents($README.'.md'));
+
+	echo '
+	</div>
+	<hr>
+	<ul class="navigationBar" >
+		<li class="navigationBar" onclick="previusPage()">&lt; &lt; Previous</li>
+		<li class="navigationBar" onclick="homePage()"> Home </li>
+		<li class="navigationBar" onclick="nextPage()">Next &gt; &gt;</li>
+	</ul>';
+
+	include($path."/footer.php");
 ?>
diff --git a/appendix/index.php b/appendix/index.php
index e8d7d64..3ee01f6 100644
--- a/appendix/index.php
+++ b/appendix/index.php
@@ -1,17 +1,23 @@
-<?php 
+<?php
 
 	$path = "..";
+	$README = "README";
+	$language = "";
+
+	if ( !empty($_GET['lan']) ) {
+		if (file_exists($README.'-'.$_GET['lan'].'.md')) {
+			$language = '-'.$_GET['lan'];
+			$README .= $language;
+		}
+	}
+
 	include($path."/header.php");
+	include($path."/chap-header.php");
+	echo '<div id="content">';
+
 	include($path."/src/parsedown/Parsedown.php");
-
-	echo '
-	<div class="header"><p><a href="https://thebookofshaders.com/">The Book of Shaders</a> by <a href="http://patriciogonzalezvivo.com">Patricio Gonzalez Vivo</a></p></div>
-	<hr>
-	<div id="content">
-	';
-
 	$Parsedown = new Parsedown();
-	echo $Parsedown->text(file_get_contents ('README.md'));
+	echo $Parsedown->text(file_get_contents($README.'.md'));
 
 	echo '
 	</div>
@@ -22,5 +28,5 @@
 		<li class="navigationBar" onclick="nextPage()">Next &gt; &gt;</li>
 	</ul>';
 
-	include($path."/footer.php"); 
+	include($path."/footer.php");
 ?>