protected static function loadCorpNegoFare($corporateNegoFare)
    {
        $opt = [];

        if ($corporateNegoFare !== null) {
            $po = new PricingOptionGroup(PricingOptionKey::OPTION_CORPORATE_NEGOTIATED_FARES);

            $po->optionDetail = new OptionDetail($corporateNegoFare);

            $opt[] = $po;
        }

        return $opt;
    }