contract FinalizableCrowdsale is Pausable {
    using SafeMath for uint256;

    bool public isFinalized = false;

    event Finalized();

    /**
     * @dev Must be called after crowdsale ends, to do some extra finalization
     * work. Calls the contract's finalization function.
     */
    function finalize() onlyOwner public {
        require(!isFinalized);

        finalization();
        Finalized();

        isFinalized = true;
    }

    /**
     * @dev Can be overridden to add finalization logic. The overriding function
     * should call super.finalization() to ensure the chain of finalization is
     * executed entirely.
     */
    function finalization() internal;
}
/**
 * @title FinalizableCrowdsale
 * @dev Extension of Crowdsale where an owner can do extra work
 * after finishing.
 */
function finalization() internal;
/**
 * @dev Can be overridden to add finalization logic. The overriding function
 * should call super.finalization() to ensure the chain of finalization is
 * executed entirely.
 */