Hai I have an xml which of this format 
<?xml version="1.0" encoding="UTF-8"?>
    <group>
    <article-ref rid="doi-ANTI_1995-63-2_001-1"/>
    <group>
    <title>America</title>
    <group>
    <title>Pakistan</title>
    <group>
    <title>India</title>
    <article-ref rid="doi-ANTI_1995-63-2_001-2"/>
    </group>
    </group>
    </group>
    <article-ref rid="doi-ANTI_1995-63-2_001-3"/>
    <group>
    <title>SYMPOSIUM: POST-CHICAGO ECONOMICS</title>
    <article-ref rid="doi-ANTI_1995-63-2_001-4"/>
    <article-ref rid="doi-ANTI_1995-63-2_001-5"/>
    <article-ref rid="doi-ANTI_1995-63-2_001-6"/>
    <article-ref rid="doi-ANTI_1995-63-2_001-7"/>
    <article-ref rid="doi-ANTI_1995-63-2_001-8"/>
    <article-ref rid="doi-ANTI_1995-63-2_001-9"/>
    <article-ref rid="doi-ANTI_1995-63-2_001-10"/>
    <article-ref rid="doi-ANTI_1995-63-2_001-11"/>
    <article-ref rid="doi-ANTI_1995-63-2_001-12"/>
    <article-ref rid="doi-ANTI_1995-63-2_001-13"/>
    </group>
    <article-ref rid="doi-ANTI_1995-63-2_001-14"/>
    </group>

[download]
This xml need be converted to the following output format 
</group>
<group>
     <group>
          <title><![CDATA[America]]></title><group>
               <title><![CDATA[Pakistan]]></title><group>
                    <title><![CDATA[India]]></title>
                    <article-ref rid="001-2"/>
               </group>
          </group>
     </group>
</group>
<group>
     <article-ref rid="001-3"/>
</group>
<group>
     <group>
          <title><![CDATA[SYMPOSIUM: POST-CHICAGO ECONOMICS]]></title>
          <article-ref rid="001-4"/>
          <article-ref rid="001-5"/>
          <article-ref rid="001-6"/>
          <article-ref rid="001-7"/>
          <article-ref rid="001-8"/>
          <article-ref rid="001-9"/>
          <article-ref rid="001-10"/>
          <article-ref rid="001-11"/>
          <article-ref rid="001-12"/>
          <article-ref rid="001-13"/>
     </group>
</group>
<group>
     <article-ref rid="001-14"/>
</group>

[download]
I could not able to get an idea where to start from. so can any one kindly suggest me what to do on this.

In reply to Group XML by ymchaitu

Title:
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