Zoho People API - two version of API, with different endpoints

Zoho People API - two version of API, with different endpoints

Hi. 

I'm working about switch my applications from auth-token authorization to OAuth. But I discover that Zoho People have TWO version of API documentation: 

https://www.zoho.com/people/help/api/overview.html - in this one, tab "Authentication token" does not work at all 
https://www.zoho.com/people/api/overview.html - in this one tab "Authentication token" is working indeed, but some API endpoints are missing, e.g. Fetch Single Record API

So my question is: how can I fetch a single record API using Oauth authentication? And why you have two versions of documentation?