Dariusz Jasak Jasak itibaren Senasalis 13200, Litvanya
I first read this book about 10 years ago, already an adult. None of the story had really stuck in my head. I just remember thinking at the time that I wish I'd read it as a kid, because clearly I was missing what was so wonderful about this book. I just re-read it with my daughter and find that I must have been right. She loved it and immediately started on the next book in the series.
This book was a fairly good introduction to the study of the complex numbers and functions of the complex numbers. One annoying feature that it had was that there were times that it stated a theorem and then proceeded without giving a proof of the theorem, not even in the appendices. Other than that however it's useful and instructive.