protected function _getVoucherSerie()
    {
        if ($this->_oVoucherSerie == null) {
            $oVoucherSerie = oxNew(\OxidEsales\Eshop\Application\Model\VoucherSerie::class);
            $sId = \OxidEsales\Eshop\Core\Registry::getConfig()->getRequestParameter("voucherid");
            if ($oVoucherSerie->load($sId ? $sId : \OxidEsales\Eshop\Core\Registry::getSession()->getVariable("voucherid"))) {
                $this->_oVoucherSerie = $oVoucherSerie;
            }
        }

        return $this->_oVoucherSerie;
    }