private function send($header = NULL, $data = NULL, $method = NULL)
    {
        $urlRequest = $this->server;

        $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL, $urlRequest);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);

        if (!is_null($header)) {
            curl_setopt($ch, CURLOPT_HTTPHEADER, $header);
        }

        if (!is_null($method)) {
            curl_setopt($ch, CURLOPT_CUSTOMREQUEST, strtoupper($method));
        }

        if (is_array($data)) {
            curl_setopt($ch, CURLOPT_POSTFIELDS, "xmlRequest=" . $data);
        }

        $output = curl_exec($ch);
        curl_close($ch);

        $xml = new SimpleXMLElement(json_decode($output, true));

        return $xml;
    }