APA (7th ed.) Citation

Gilbert, A. (1971). Knock, knock! who's there? White Lion.

Chicago Style (17th ed.) Citation

Gilbert, Anthony. Knock, Knock! Who's There? London: White Lion, 1971.

MLA (8th ed.) Citation

Gilbert, Anthony. Knock, Knock! Who's There? White Lion, 1971.

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