It really was like the first 7 chapters of a 10 chapter book I already own, but made slightly more long winded. And it was a Dutch translation of a French book, not sure if it was ever translated to English.

It's this one:

https://www.abebooks.co.uk/Encyclope...20204866173/bd

Apparently it should be in two parts. Hmmm next time I'm at the shop I'll check if it indeed has the "1" on it. I wonder what's in part two, given they covered almost everything in part 1 already. They didn't have any part 2 in the shop though.