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