New 'Cost center' funtionality REST API

Good day

I was given a task to implement new 'Cost center' functionality of the SDL translation on the project i work on. 

Sadly, documentation is not updated, so i have no idea where to start.

I know 2 things

  1. there is a call to get a list of 'cost centers'
  2. the selected cost center will be used when creating a project

If anyone can shed ANY light on this, i would be eternally grateful

Thank you in advance