Lua APA (7ú heag.)
Brown, L. R. (1991). State of the world 1991: A worldwatch institute report on progress toward a sustainable society. W.W. Norton & Co..
Lua i Stíl Chicago (17ú heag.)
Brown, Lester R. State of the World 1991: A Worldwatch Institute Report on Progress Toward a Sustainable Society. New York: W.W. Norton & Co., 1991.
Lua MLA (9ú heag.)
Brown, Lester R. State of the World 1991: A Worldwatch Institute Report on Progress Toward a Sustainable Society. W.W. Norton & Co., 1991.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.