APA (7th ed.) Citation

Calvino, I., & Weaver, W. (1982). If on a winter's night a traveller. Picador.

Chicago Style (17th ed.) Citation

Calvino, Italo, and William Weaver. If on a Winter's Night a Traveller. London: Picador, 1982.

MLA (9th ed.) Citation

Calvino, Italo, and William Weaver. If on a Winter's Night a Traveller. Picador, 1982.