public function &GetValidPaymentMethods($bRefresh = false)
    {
        if (is_null($this->oValidPaymentMethods) || $bRefresh) {
            $this->oValidPaymentMethods = &TdbShopPaymentMethodList::GetAvailableMethods($this->id);
            $this->oValidPaymentMethods->bAllowItemCache = true;
        }
        if (!is_null($this->oValidPaymentMethods)) {
            $this->oValidPaymentMethods->GoToStart();
        }

        return $this->oValidPaymentMethods;
    }