APA (7th ed.) Citation

De Bono, E. (1967). The 5 day course in thinking: Introducing the L game. Penguin.

Chicago Style (17th ed.) Citation

De Bono, Edward. The 5 Day Course in Thinking: Introducing the L Game. Harmondsworth: Penguin, 1967.

MLA (8th ed.) Citation

De Bono, Edward. The 5 Day Course in Thinking: Introducing the L Game. Penguin, 1967.