Oauth 2.0 example

Hi,

I'm looking for an Oauth 2.0 example. I have an integration with Moneybird (https://www.moneybird.com/) and they changed the authentication to Oauth 2.0. Does anybody have an integration using Oauth 2.0 that he wants to share with me? The integration with Moneybird is supposed to be build with REST.

Thanks.
Toon Verschoor