eBook confirmation for ITIL-F

Hi everyone, since I failed my ITIL-F by 3 questions, I decided to do it again since I have invested a lot of time into it. Since I encountered a lot of ambiguity in the questions, I think I need to study again and tie up any loose ends. I purchased Claire Agutter's ebook ITIL Foundation Essentials. I noticed after skimming through it that it seems to address some of the ambiguity I encountered on the exam.
Can anyone confirm that this ebook was helpful for the exam?
There is another book by a Liz Gallacher but it seems huge to me.
Thanks
Can anyone confirm that this ebook was helpful for the exam?
There is another book by a Liz Gallacher but it seems huge to me.
Thanks