{ "metadata": { "title": "A Sample Book", "identifier": "urn:isbn:1234567890" }, "links": [ { "href": "https://example.org/book.epub", "type": "application/epub+zip", "rel": "http://opds-spec.org/acquisition" } ], "images": [ { "href": "https://example.org/cover.jpg", "type": "image/jpeg" } ] }