Cita APA (7a ed.)
(1991). State of the World 1991: <A> Worldwatch Institute Report on Progress Toward a Sustainable Society (1. ed.). Norton and Co.
Cita Chicago Style (17a ed.)
State of the World 1991: <A> Worldwatch Institute Report on Progress Toward a Sustainable Society. 1. ed. New York: Norton and Co, 1991.
Cita MLA (9a ed.)
State of the World 1991: <A> Worldwatch Institute Report on Progress Toward a Sustainable Society. 1. ed. Norton and Co, 1991.
Precaución: Estas citas no son 100% exactas.