APA (7th ed.) Citation

DE BONO. (1990). The happiness purpose. London: Penguin Books, 1990.

Chicago Style (17th ed.) Citation

DE BONO. The Happiness Purpose. London: London: Penguin Books, 1990, 1990.

MLA (8th ed.) Citation

DE BONO. The Happiness Purpose. London: Penguin Books, 1990, 1990.

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