This book is good as a very basic introduction to Box Turtles and Tortoises. The pictures are good and some of the advice on certain species is worth while.
However, there is some very bad information included. As anexample, increasing the humidity for a Star Tortoise. This advice will secure large vet bills for you from the respiratory issues your Star will certainly develop. Another is keepng your tortoise in a glass aquarium or glass sided enclosure.
I doubt the auther has any real-life experience with many of the tortoise species he mentions in this book. If he did, most will be quite ill or no longer with us.