code: public function getIncoming($domain, $id)
      {
          if (!$domain)
              throw new BadMethodCallException('Parameter $domain is missing.');
          if ($id !== 0 && !$id)
              throw new BadMethodCallException('Parameter $id is missing.');
          $id = intval($id);
          try {
              $r = $this->get('sms/' . $domain . '/incoming/' . $id)->send();
          } catch (\Exception $e) {
              throw new SmsException($e->getMessage(), $e->getCode(), $e);
          }
  
          return $r->getBody(true);
      }
docs: Get history object properties
  
  @param string $domain
  @param integer $id
  @return string Json
  @throws BadMethodCallException
  @throws Exception\SmsException