Barrett, J., & Willams, G. (2002). Test your own aptitude. Kogan Page.
Cita Chicago (17th ed.)Barrett, Jim, i Geoff Willams. Test Your Own Aptitude. New Delhi: Kogan Page, 2002.
Cita MLA (8th ed.)Barrett, Jim, i Geoff Willams. Test Your Own Aptitude. Kogan Page, 2002.
Atenció: Aquestes cites poden no estar 100% correctes.