APA (7th ed.) Citation

Wyndham, J. (1951). The Day of the Triffids. Penguin Books.

Chicago Style (17th ed.) Citation

Wyndham, John. The Day of the Triffids. London: Penguin Books, 1951.

MLA (9th ed.) Citation

Wyndham, John. The Day of the Triffids. Penguin Books, 1951.

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