Cita APA (7a ed.)
Worldwatch Institute. Vital Signs, Volume 20: The Trends That Are Shaping Our Future. Island Press.
Cita estilo Chicago (17a ed.)
Worldwatch Institute. Vital Signs, Volume 20: The Trends That Are Shaping Our Future. Washington, EUA: Island Press.
Cita MLA (9a ed.)
Worldwatch Institute. Vital Signs, Volume 20: The Trends That Are Shaping Our Future. Island Press.
Precaución: Estas citas no son 100% exactas.