Train the Brain: Use It or Lose It

The 33 Strategies of War

Becoming Bulletproof: Protect Yourself, Read People, Influence Situations, and Live Fearlessly

Sherlock Holmes Case-book of Curious Puzzles: A Collection of Enigmas to Puzzle even the Greatest Detective

Think Again: The Power of Knowing What You Don't Know

The Amazing Sherlock Holmes Puzzle Book: A Cornucopia of Conundrums Inspired by the World's Greatest Detective

How to Sell Anything to Anybody

The Penguin Book of Puzzles: Solve these wonderfully perplexing logic puzzles

Tutankhamun and the Puzzles of Ancient Egypt

Working With Emotional Intelligence

Leonardo da Vinci Puzzles: Creative Challenges Inspired by the Master of the Renaissance

To Sell Is Human: The Surprising Truth About Moving Others

Lateral Logic: Puzzle Your Way to Smart Thinking

Building a Second Brain: A Proven Method to Organise Your Digital Life and Unlock Your Creative Potential

Einstein Puzzles: Brain Stretching Challenges Inspired by the Scientific Genius

Financial Intelligence, Revised Edition: A Manager's Guide to Knowing What the Numbers Really Mean

Sherlock Holmes Compendium of Mysterious Puzzles

Success Is a Choice: Make the Choices that Make You Successful

Edgar Allan Poe Puzzles: Puzzles of Mystery and Imagination

Hyperfocus: How to Manage Your Attention in a World of Distraction