Exhibit 5

Joint Filing Agreement

Pursuant to Rule 13d-1(f)(1) under the Securities Exchange Act of 1934, as amended, the undersigned hereby agree to the joint filing with each other of an Amendment No. 1 to Schedule 13D, with respect to each holding as to which such a report must be made, and that each such Schedule and all amendments thereto are made on behalf of each of them.

This Agreement may be executed in any number of counterparts, each of which shall be deemed an original and all of which shall together constitute the same agreement.

Executed this 13th day of December, 2011.

BERTELSMANN AG

By: /s/ Martin Dannhoff                           
       Martin Dannhoff 
       Senior Vice President

By: /s/ Michael Kronenburg                    
       Michael Kronenburg 
       Senior Vice President

BERTELSMANN ASIA INVESTMENTS AG

By: /s/ Erich Kalt                                       
       Erich Kalt 
       Authorized Signatory

By: /s/ Rose-Marie Mülli                          
       Rose-Marie Mülli 
       Authorized Signatory