"parent": null,
"cover_color": "#a6820a",
"simple_cover": "http://testserver/media/simple_cover/parent.jpg",
"parent": null,
"cover_color": "#a6820a",
"simple_cover": "http://testserver/media/simple_cover/parent.jpg",
"audio_length": "1:00",
"epub": "http://testserver/media/epub/parent.epub",
"cover_thumb": "http://testserver/media/cover/parent.jpg-139x193",
"audio_length": "1:00",
"epub": "http://testserver/media/epub/parent.epub",
"cover_thumb": "http://testserver/media/cover/parent.jpg-139x193",
"url": "http://testserver/katalog/lektura/parent/",
"cover": "http://testserver/media/cover/parent.jpg",
"pdf": "http://testserver/media/pdf/parent.pdf",
"url": "http://testserver/katalog/lektura/parent/",
"cover": "http://testserver/media/cover/parent.jpg",
"pdf": "http://testserver/media/pdf/parent.pdf",