Chessboard Illusion %28Checker Shadow Illusion%29
Here's your citation in American Psychological Association (APA) format:
Chessboard Illusion %28Checker Shadow Illusion%29. (n.d.). In Alleydog.com's online glossary. Retrieved from: https://www.alleydog.com/glossary/definition-cit.php?term=Chessboard+Illusion+%2528Checker+Shadow+Illusion%2529