PHPOffice / PhpSpreadsheet

        $this->documentSummaryInformation = $this->writeDocumentSummaryInformation();

        // initialize OLE Document Summary Information

        if (isset($this->documentSummaryInformation) && !empty($this->documentSummaryInformation)) {

            $OLE_DocumentSummaryInformation = new \PhpOffice\PhpSpreadsheet\Shared\OLE\PPS\File(\PhpOffice\PhpSpreadsheet\Shared\OLE::ascToUcs(chr(5) . 'DocumentSummaryInformation'));

            $OLE_DocumentSummaryInformation->append($this->documentSummaryInformation);

        }

        $this->summaryInformation = $this->writeSummaryInformation();

        // initialize OLE Summary Information

        $this->summaryInformation = $this->writeSummaryInformation();

        // initialize OLE Summary Information

        if (isset($this->summaryInformation) && !empty($this->summaryInformation)) {

            $OLE_SummaryInformation = new \PhpOffice\PhpSpreadsheet\Shared\OLE\PPS\File(\PhpOffice\PhpSpreadsheet\Shared\OLE::ascToUcs(chr(5) . 'SummaryInformation'));

            $OLE_SummaryInformation->append($this->summaryInformation);

        }

        // define OLE Parts

        $arrRootData = [$OLE];