protected function _addPageNrParam($url, $page, $languageId = null)
    {
        if ($page) {
            if ((strpos($url, 'pgNr='))) {
                $url = preg_replace('/pgNr=[0-9]*/', 'pgNr=' . $page, $url);
            } else {
                $url .= ((strpos($url, '?') === false) ? '?' : '&amp;') . 'pgNr=' . $page;
            }
        } else {
            $url = preg_replace('/pgNr=[0-9]*/', '', $url);
            $url = preg_replace('/\&amp\;\&amp\;/', '&amp;', $url);
            $url = preg_replace('/\?\&amp\;/', '?', $url);
            $url = preg_replace('/\&amp\;$/', '', $url);
        }

        return $url;
    }