Style de citation APA (7e éd.)
(1991). State of the World 1991: <A> Worldwatch Institute Report on Progress Toward a Sustainable Society (1. ed.). Norton and Co.
Style de citation Chicago (17e éd.)
State of the World 1991: <A> Worldwatch Institute Report on Progress Toward a Sustainable Society. 1. ed. New York: Norton and Co, 1991.
Style de citation MLA (9e éd.)
State of the World 1991: <A> Worldwatch Institute Report on Progress Toward a Sustainable Society. 1. ed. Norton and Co, 1991.
Attention : ces citations peuvent ne pas être correctes à 100%.