law: Sashastra Seema Bal Act, 2007 
  106.  Presumption as to signatures.
  In any proceeding under this Act, any application, certificate,
  
  warrant, reply or other document purporting to be signed by an officer in the
  
  service of the Government shall, on production, be presumed to have been duly
  
  signed by the person by whom and in the character in which it purports to have
  
  been signed, until the contrary is shown.