  function _transfer(address _from, address _to, uint _value) internal {
    require(_to != address(0x0));
    require(checkFrozenWallet(_from, _value));
    balanceOf[_from] = balanceOf[_from].sub(_value);      
    balanceOf[_to] = balanceOf[_to].add(_value);     
    emit Transfer(_from, _to, _value);
  }