Kwik, J. (2020). Limitless: Upgrade your brain, learn anything faster, and unlock your exceptional life (1st edition.). Hay House, Inc..
Chicago-viite (17. p.)Kwik, Jim. Limitless: Upgrade Your Brain, Learn Anything Faster, and Unlock Your Exceptional Life. 1st edition. Carlsbad, California: Hay House, Inc., 2020.
MLA-viite (9. p.)Kwik, Jim. Limitless: Upgrade Your Brain, Learn Anything Faster, and Unlock Your Exceptional Life. 1st edition. Hay House, Inc., 2020.
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