    function closeIco() public onlyOwner {
        require(!isIcoComplete, "The ICO phase has already ended, you cannot close it again.");
        require((balances[owner] - rewardPool_) == 0, "Cannot close ICO when a balance remains in the owner account.");
        isIcoComplete = true;
        delete kycHashes;
        delete kycValidated;
        emit IcoComplete();
    }