Nathan Haselbauer

Nathan Haselbauer, President of the International High IQ Society, has painstakingly researched and designed this impressively varied collection of over 500 mind-bending puzzles to enable…

A brilliant, new collection of quick brain teasers offering satisfaction in moments! This giant volume offers hundreds of original new puzzles ranging from easy maths…

Make the most of yourself! There are so many different kinds of intelligence - no single test can cover them. Do you have a way…

Here is the biggest and most varied book of Sudoku puzzles ever compiled. Over 400 painstakingly prepared puzzles designed to satisfy all levels from beginner…

With this brain-teasing new collection of tantalizing puzzles and top-grade problems, Nathan Haselbauer, mastermind behind the test for the world's most intelligent person, throws open…