Taya , Shuichiro, and Masaya Ishikawa. “The Bumpy Circle Illusion: Apparent Shape-Distortion of Filled Circles Placed on a Checkered Pattern”. Journal of Illusion 4 (January 25, 2024). Accessed April 1, 2026. https://journalofillusion.net/index.php/joi/article/view/9658.