diff --git a/datalets.xml b/datalets.xml
index e9c17a2..d35250b 100755
--- a/datalets.xml
+++ b/datalets.xml
@@ -1,6 +1,14 @@
 <?xml version="1.0" encoding="utf-8"?>
+
+<!DOCTYPE handler_configuration SYSTEM "datalets/datalets.dtd" [
+    <!ENTITY googlePiechart SYSTEM "datalets/googlePiechart.xml">
+]>
+
 <handler_configuration>
     <components>
+
+        <!--&googlePiechart;-->
+
        <component>
            <name>datatable-datalet</name>
            <attributes>
@@ -53,10 +61,6 @@
                     </input>
                     <layouts>
                         <input>
-                            <name>title</name>
-                            <description>The label for the title of the chart</description>
-                        </input>
-                        <input>
                             <name>x-axis-label</name>
                             <description>The label for the X axis</description>
                         </input>
@@ -100,10 +104,6 @@
                     </input>
                     <layouts>
                         <input>
-                            <name>title</name>
-                            <description>The label for the title of the chart</description>
-                        </input>
-                        <input>
                             <name>x-axis-label</name>
                             <description>The label for the X axis</description>
                         </input>
@@ -147,10 +147,6 @@
                     </input>
                     <layouts>
                         <input>
-                            <name>title</name>
-                            <description>The label for the title of the chart</description>
-                        </input>
-                        <input>
                             <name>x-axis-label</name>
                             <description>The label for the X axis</description>
                         </input>
@@ -194,10 +190,6 @@
                     </input>
                     <layouts>
                         <input>
-                            <name>title</name>
-                            <description>The label for the title of the chart</description>
-                        </input>
-                        <input>
                             <name>x-axis-label</name>
                             <description>The label for the X axis</description>
                         </input>
@@ -241,10 +233,6 @@
                     </input>
                     <layouts>
                         <input>
-                            <name>title</name>
-                            <description>The label for the title of the chart</description>
-                        </input>
-                        <input>
                             <name>x-axis-label</name>
                             <description>The label for the X axis</description>
                         </input>
@@ -302,10 +290,6 @@
                     </input>
                     <layouts>
                         <input>
-                            <name>title</name>
-                            <description>The label for the title of the chart</description>
-                        </input>
-                        <input>
                             <name>x-axis-label</name>
                             <description>The label for the X axis</description>
                         </input>
@@ -345,17 +329,13 @@
                         <selection>11</selection>
                     </input>
                     <input>
-                        <name>Size </name>
+                        <name>Size</name>
                         <description>The size for each series to create a concentric rings</description>
                         <scale>nominal</scale>
                         <role>domain</role>
                         <selection>11</selection>
                     </input>
                     <layouts>
-                        <input>
-                            <name>title</name>
-                            <description>The label for the title of the chart</description>
-                        </input>
                     </layouts>
                 </inputs>
             </idm>
@@ -387,10 +367,6 @@
                         <selection>11</selection>
                     </input>
                     <layouts>
-                        <input>
-                            <name>title</name>
-                            <description>The label for the title of the chart</description>
-                        </input>
                     </layouts>
                 </inputs>
             </idm>
@@ -415,10 +391,6 @@
                         <selection>*</selection>
                     </input>
                     <layouts>
-                        <input>
-                            <name>name</name>
-                            <description>The name of the treemap</description>
-                        </input>
                     </layouts>
                 </inputs>
             </idm>
@@ -461,25 +433,5 @@
                 </inputs>
             </idm>
         </component>
-        <!--<component>
-            <name>preview-datalet</name>
-            <attributes>
-                <attribute>
-                    <name>data-url</name>
-                </attribute>
-            </attributes>
-            <idm>
-                <inputs>
-                    <input>
-                    </input>
-                    <layouts>
-                        <input>
-                            <name>url</name>
-                            <description>The url of the page you want put in the preview</description>
-                        </input>
-                    </layouts>
-                </inputs>
-            </idm>
-        </component>-->
-    </components>    
+    </components>
 </handler_configuration>
diff --git a/datalets/datalets.dtd b/datalets/datalets.dtd
new file mode 100644
index 0000000..7c08687
--- /dev/null
+++ b/datalets/datalets.dtd
@@ -0,0 +1,17 @@
+<!ELEMENT handler_configuration (components)>
+<!ELEMENT components (component*)>
+<!ELEMENT component (name, attributes, idm)>
+<!ELEMENT attributes (attribute*)>
+<!ELEMENT attribute (name)>
+<!ELEMENT idm (inputs*)>
+<!ELEMENT inputs (input*, layouts)>
+<!ELEMENT layouts (input*)>
+<!ELEMENT input (name, description?, scale?, role?, selection?, type?, validator?)>
+<!ELEMENT name (#PCDATA)>
+<!ELEMENT description (#PCDATA)>
+<!ELEMENT scale (#PCDATA)>
+<!ELEMENT role (#PCDATA)>
+<!ELEMENT selection (#PCDATA)>
+<!ELEMENT type (#PCDATA)>
+<!ELEMENT validator (#PCDATA)>
+
diff --git a/datalets/googlePiechart.xml b/datalets/googlePiechart.xml
new file mode 100755
index 0000000..b7a8802
--- /dev/null
+++ b/datalets/googlePiechart.xml
@@ -0,0 +1,47 @@
+<component>
+    <name>google_piechart-datalet</name>
+    <attributes>
+        <attribute>
+            <name>data-url</name>
+        </attribute>
+        <attribute>
+            <name>fields</name>
+        </attribute>
+    </attributes>
+    <idm>
+        <inputs>
+            <input>
+                <name>Labels</name>
+                <description>googlePiechartDescription</description>
+                <scale>nominal</scale>
+                <role>domain</role>
+                <selection>11</selection>
+            </input>
+            <input>
+                <name>Values</name>
+                <description>The sizes of slices.</description>
+                <scale>nominal</scale>
+                <role>domain</role>
+                <selection>11</selection>
+            </input>
+            <layouts>
+                <input>
+                    <name>_title</name>
+                    <description>The label for the title of the chart</description>
+                    <type>String</type>
+                </input>
+                <input>
+                    <name>pieHole</name>
+                    <description>You can create donut charts with this option; it is the size of the hole and it has a range between 0 and 1.</description>
+                    <type>Number</type>
+                    <validator>[0,1]</validator>
+                </input>
+                <input>
+                    <name>is3D</name>
+                    <description>You can create 3D charts with this option; if "true" pieHole will be ignored.</description>
+                    <type>Boolean</type>
+                </input>
+            </layouts>
+        </inputs>
+    </idm>
+</component>
\ No newline at end of file