Mind your step is a street illusion in Stockholm at Sergels torg created by Erik Johansson.
- Girl on a Path: Mind-Bending Optical Illusion (boredpanda.com)
- Optical Illusion Dresses (simplybeblog.co.uk)
- New Optical Illusions Expose More Foibles of the Brain | Best Illusions of 2012 (illuminutti.com)
- Mind-blowing Arts – Optical Illusions (micernest.wordpress.com)
- “Oldboy” Optical Illusion (moillusions.com)