APA (7th ed.) Citation

Opie, I. A., Opie, P., & Hassall, J. (1955). The Oxford nursery rhyme book. Clarendon Press.

Chicago Style (17th ed.) Citation

Opie, Iona Archibald, Peter Opie, and Joan Hassall. The Oxford Nursery Rhyme Book. Oxford: Clarendon Press, 1955.

MLA (8th ed.) Citation

Opie, Iona Archibald, et al. The Oxford Nursery Rhyme Book. Clarendon Press, 1955.