Cita APA (7a ed.)

Sinek, S. (2011). Start with why: How great leaders inspire everyone to take action. Portfolio Penguin.

Cita Chicago Style (17a ed.)

Sinek, Simon. Start with Why: How Great Leaders Inspire Everyone to Take Action. London [etc.]: Portfolio Penguin, 2011.

Cita MLA (9a ed.)

Sinek, Simon. Start with Why: How Great Leaders Inspire Everyone to Take Action. Portfolio Penguin, 2011.