public function css($aliasOrUrl, array $attributes = [])
    {
        $url = $this->getCssUrl($aliasOrUrl);
        if (!$this->included->isIncluded($url)) {
            $this->included->markAsIncluded($url);
            return new Tag('link', array_merge([
                'type' => 'text/css',
                'rel' => 'stylesheet',
                'href' => $url,
                'media' => 'all'
            ], $attributes));
        } else {
            return new DataView();
        }
    }