When your mind is distracted simply pick up this collection of 70 intricate optical illusions and reach for your colouring pencils. There are absolutely no rules - simply choose a design at random, choose any combination of colours you like, and get started. As you concentrate on the simple action of colouring in, you will find calm returning. The sheets in this pad are all detachable, so you can display your favourite creations. Это и многое другое вы найдете в книге Optical Illusions: 70 Designs to Help You De-Stress