APA (7th ed.) Citation

Thompson, R. P., Baum, L. F., & Neill, J. R. (2009). The Royal Book of Oz In which the Scarecrow goes to search for his family tree and discovers that he is the Long Lost Emperor of the Silver Island. Project Gutenberg.

Chicago Style (17th ed.) Citation

Thompson, Ruth Plumly, L. Frank Baum, and John R. Neill. The Royal Book of Oz In Which the Scarecrow Goes to Search for His Family Tree and Discovers That He Is the Long Lost Emperor of the Silver Island. Project Gutenberg, 2009.

MLA (9th ed.) Citation

Thompson, Ruth Plumly, et al. The Royal Book of Oz In Which the Scarecrow Goes to Search for His Family Tree and Discovers That He Is the Long Lost Emperor of the Silver Island. Project Gutenberg, 2009.

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