function getAttributions( $content ) {
		$media_in_page = get_media_embedded_in_content( $content );

		// these are not the droids you're looking for
		if ( empty( $media_in_page ) ) {
			return $content;
		}

		// get all book attachments
		$book_media = $this->getBookMedia();
		if ( ! empty( $book_media ) ) {
			$media_ids = Media\extract_id_from_media( $media_in_page );
			// intersect media_ids found in page with found in book
			$unique_ids = Media\intersect_media_ids( $media_ids, $book_media );
		} else {
			return $content;
		}

		// get attribution meta for each attachment
		$all_attributions = $this->getAttributionsMeta( $unique_ids );

		// get the content of the attributions
		$media_attributions = $this->attributionsContent( $all_attributions );

		return $content . $media_attributions;
	}