SINEK, Simon; MEAD, David a DOCKER, Peter. Find your why: a practical guide to discovering purpose for you or your team. [London]: Portfolio Penguin, 2017. ISBN 9780241279267.
APA CSE CSE NY ČSN ISO 690:2022 (číslování) ČSN ISO 690:2022 - autor, datum Harvard Chicago (16th edition) IEEE ISO 690 MLA (7th edition) Turabian (7th edition)