Difficult Nurikabe book: 200 puzzles

Welcome to Nurikabe!
This book is intended for experienced Nurikabe solvers, who need a real challenge. All 200 puzzles in this book are hard and require you to apply various Nurikabe solving techniques. Some of the solving methods for Nurikabe puzzles are explained in the introduction. Guessing is never required and all puzzles have one solution only. The solutions are at the back of the book.
Puzzles range from 9×9 to massive 20×20 in size. They will surely provide hours of fun for a true Nurikabe puzzler!
Have fun!