public function showArticles (string $lang, string $year = null, string $month = null, string $day = null, string $slug = null)
    {
        //URL -> articles/2017/03/23/page-name
        if ($slug)
            return $this->showArticle($lang, $year, $month, $day, $slug);

        if ($day)
            return $this->showByDate((new Carbon($year . '-' . $month . '-' . $day))->startOfDay(), (new Carbon($year . '-' . $month . '-' . $day))->endOfDay());

        if ($month)
            return $this->showByDate((new Carbon($year . '-' . $month))->startOfMonth(), (new Carbon($year . '-' . $month))->endOfMonth());

        if ($year)
            return $this->showByDate((new Carbon($year))->startOfYear(), (new Carbon($year))->endOfYear());

        abort(404, 'Page not found');
    }