Cita APA (7th ed.)

Villanueva, R., Dulce, L., & Guzman, R. B. (2012). Rio+20: United Nations Conference on Sustainable Development. DZUP.

Cita Chicago (17th ed.)

Villanueva, Raymund, Leon Dulce, i Rosario Bella Guzman. Rio+20: United Nations Conference on Sustainable Development. Quezon City: DZUP, 2012.

Cita MLA (9th ed.)

Villanueva, Raymund, et al. Rio+20: United Nations Conference on Sustainable Development. DZUP, 2012.