Different editions or different books?

[Marcos]

Imagine an original book (e.g "Geology") that is later separated (either in the same lenguaje or different lenguajes) into three different books (e.g, "Geology I. Earth", "Geology II. The seas" etc...). Should they be added as new editions or new books? Thanks!

[Krazykiwi]

This is very common with translations.

Yes, add them as separate editions, they do not individually contain the same content as the entire original book, only part of it.