# Implement Strong Customer Authentication (SCA) and Payment Intents with an older API version

The Payment Intents API works on all API versions. However, depending on the API version you are using, you may need to adjust your code.
### API Version 2019-02-11 or Older
If you are using an API version older than 2019-02-11, make note of the following two changes as you go through the code examples and implementation process:
* `requires_source` has been renamed to `requires_payment_method`
* `requires_source_action` has been renamed to `requires_action`
## Additional Information
* If you are using one of [Stripe's API libraries](https://stripe.com/docs/libraries), you will need to upgrade to the latest version of the library in order to use the Payment Intents API.