Paperback (Offset Printed)
This is the higher quality version, but since it is printed in batches with a traditional printing press, the production time is slower, and it may be out of stock.

Paperback (Print On-Demand)
The quality of this book is not as good as the Offset Printed version, but it is produced using Amazon’s print on-demand service, so it will always be in stock.

Kindle
Cheaper eBook version