APA (7th ed.) Citation

Marzollo, J., & Wick, W. (2001). I spy, year-round challenger!: A book of picture riddles. Scholastic.

Chicago Style (17th ed.) Citation

Marzollo, Jean, and Walter Wick. I Spy, Year-round Challenger!: A Book of Picture Riddles. New York: Scholastic, 2001.

MLA (8th ed.) Citation

Marzollo, Jean, and Walter Wick. I Spy, Year-round Challenger!: A Book of Picture Riddles. Scholastic, 2001.

Warning: These citations may not always be 100% accurate.