public function getDeliveryColumns()
    {
        $columns = [];

        // add custom properties, it contains the group property as well
        $customProps = $this->getClass($this->delivery->getOnePropertyValue($this->getProperty(OntologyRdf::RDF_TYPE)))->getProperties();

        $deliveryProps = array_merge($this->deliveryProperties, $customProps);

        foreach ($deliveryProps as $property){
            $property = $this->getProperty($property);
            $loginCol = new ContextTypePropertyColumn(ContextTypePropertyColumn::CONTEXT_TYPE_DELIVERY, $property);

            if ($property->getUri() == OntologyRdfs::RDFS_LABEL) {
                $loginCol->label = __('Delivery');
            }

            $columns[] = $loginCol->toArray();
        }

        return $columns;
    }