PhpOffice\PhpPresentation\Writer\PowerPoint2007\Relationships::writePresentationRelationships PHP Method

    public function writePresentationRelationships()
    {
        // Create XML writer
        $objWriter = new XMLWriter(XMLWriter::STORAGE_MEMORY);
        // XML header
        $objWriter->startDocument('1.0', 'UTF-8', 'yes');
        // Relationships
        $objWriter->startElement('Relationships');
        $objWriter->writeAttribute('xmlns', 'http://schemas.openxmlformats.org/package/2006/relationships');
        // Relation id
        $relationId = 1;
        foreach ($this->getPresentation()->getAllMasterSlides() as $oMasterSlide) {
            // Relationship slideMasters/slideMasterX.xml
            $this->writeRelationship($objWriter, $relationId++, 'http://schemas.openxmlformats.org/officeDocument/2006/relationships/slideMaster', 'slideMasters/slideMaster' . $oMasterSlide->getRelsIndex() . '.xml');
        }
        // Add slide theme (only one!)
        // Relationship theme/theme1.xml
        $this->writeRelationship($objWriter, $relationId++, 'http://schemas.openxmlformats.org/officeDocument/2006/relationships/theme', 'theme/theme1.xml');
        // Relationships with slides
        $slideCount = $this->getPresentation()->getSlideCount();
        for ($i = 0; $i < $slideCount; ++$i) {
            $this->writeRelationship($objWriter, $relationId++, 'http://schemas.openxmlformats.org/officeDocument/2006/relationships/slide', 'slides/slide' . ($i + 1) . '.xml');
        }
        $this->writeRelationship($objWriter, $relationId++, 'http://schemas.openxmlformats.org/officeDocument/2006/relationships/presProps', 'presProps.xml');
        $this->writeRelationship($objWriter, $relationId++, 'http://schemas.openxmlformats.org/officeDocument/2006/relationships/viewProps', 'viewProps.xml');
        $this->writeRelationship($objWriter, $relationId++, 'http://schemas.openxmlformats.org/officeDocument/2006/relationships/tableStyles', 'tableStyles.xml');
        // Comments Authors
        foreach ($this->getPresentation()->getAllSlides() as $oSlide) {
            foreach ($oSlide->getShapeCollection() as $oShape) {
                if (!$oShape instanceof Comment) {
                    continue;
                }
                $oAuthor = $oShape->getAuthor();
                if (!$oAuthor instanceof Author) {
                    continue;
                }
                $this->writeRelationship($objWriter, $relationId++, 'http://schemas.openxmlformats.org/officeDocument/2006/relationships/commentAuthors', 'commentAuthors.xml');
                break 2;
            }
        }
        $objWriter->endElement();
        // Return
        return $objWriter->getData();
    }