public function showChannelsTypes($limit = null, $offset = null)
    {

        if ($limit!= null && $limit < 1) {
            throw new InvalidArgumentException(
                "Api::showChannelsTypes() limit must be a min 1 ");
        }
        if ($offset!= null && $offset < 0) {
            throw new InvalidArgumentException(
                "Api::showChannelsTypes() $offset must be a positive number,  min 0 ");
        }

        /** @var $command \Guzzle\Service\Command\AbstractCommand */
        $command = $this->client->getCommand('GetChannelsType',array('limit'=>$limit,'offset'=>$offset));

        return $this->executeCommand($command);
    }