I returned this book. These are the reasons:
The text was completely illegible, probably due to a general coding error. There is any quality control, just flipping through the pages, the error was already visible. It's absolutely unacceptable. It was a completely unusable copy.
Moreover, my copy was completely different that the preview that you can see at amazon.uk web. The preview is from the abridged edition in one volume. But the text that GBBooks sent me seems correspond to the third volume of the complete edition in three volumes. Sorry, but all was a disaster.