Cita APA (7a ed.)

Veenhoven, R. (1989). Conditions of happiness. D. Reidel.

Cita Chicago Style (17a ed.)

Veenhoven, Ruut. Conditions of Happiness. Dordrecht [etc.]: D. Reidel, 1989.

Cita MLA (9a ed.)

Veenhoven, Ruut. Conditions of Happiness. D. Reidel, 1989.