APA (7th ed.) Citation

Ainsworth, A., & Holmes, S. The ugly duckling. Ladybird Books Ltd.

Chicago Style (17th ed.) Citation

Ainsworth, Alison, and Stephen Holmes. The Ugly Duckling. USA: Ladybird Books Ltd.

MLA (9th ed.) Citation

Ainsworth, Alison, and Stephen Holmes. The Ugly Duckling. Ladybird Books Ltd.

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