Add any SDK to Laravel 5.x

I'm trying to add this SDK in my Laravel 5.4 application. I downloaded and installed it in app/resources/assets and guessing that I can use it in controllers as:

require_once '[ruta/payu-php-sdk]/lib/PayU.php';

The SDK have some Eviromental variables and Keys.

What do you think is the better approach for this type of SDK in laravel?

via Chebli Mohamed