private function setAuthMethod($authMethod)
    {
        switch ($authMethod) {
            case 'apikey':
                $this->curl->setHeader('X-API-KEY', $this->apiKey);
                break;

            case 'basic':
            default:
                $this->curl->setBasicAuthentication($this->apiUsername, $this->apiPassword);
                break;
        }
    }