By A Mystery Man Writer
Explaining Optical Illusions: Part 6 - The Hering Illusion and the Lilac Chaser Illusion
Wundt Illusion, Optical Illusions Wiki
Optical illusion - Wikipedia
upload.wikimedia.org/wikipedia/commons/thumb/5/57/
Mind Games: How Optical Illusions Can Fool Your Brain! - Discovery Express
Lined & Unlined · A Wikipedia Reader
Hering illusion, Psychology Wiki
Colin Foster's Mathematics Education Blog: Motivation for measurement
Mind Games: How Optical Illusions Can Fool Your Brain! - Discovery Express