Redux Normalizr.js: How to Organize Data in Stores, Part 2

In this article, I want to continue on the topic of using Normalizr in a React-Redux application and finally answer the question about an all-purpose API which was mentioned briefly in the previous article.
To remind you what that article was about, Normalizr is a utility that normalizes data represented by nested entities (like in server responses), so that it can be stored and used later just as if there was a copy of a database on the front-end (e.g. in the Redux store). In Part I, we had an example with the entity relations described by this diagram: