Cita APA (7th ed.)
Halpern, D. (2011). The hidden wealth of nations. Policy Press.
Cita Chicago (17th ed.)
Halpern, D. The Hidden Wealth of Nations. Cambridge: Policy Press, 2011.
Cita MLA (9th ed.)
Halpern, D. The Hidden Wealth of Nations. Policy Press, 2011.
Atenció: Aquestes cites poden no estar 100% correctes.