APA (7th ed.) Zitazioa
Brown, L. R., & Starke, L. State of the World 1999: A Worldwatch Institute Report on Progress Toward a Sustainable Society. Norton : Worldwatch Institute.
Chicago Style (17th ed.) Zitazioa
Brown, Lester R., eta Linda Starke. State of the World 1999: A Worldwatch Institute Report on Progress Toward a Sustainable Society. Nueva York, EUA: Norton : Worldwatch Institute.
MLA (9th ed.) Zitazioa
Brown, Lester R., eta Linda Starke. State of the World 1999: A Worldwatch Institute Report on Progress Toward a Sustainable Society. Norton : Worldwatch Institute.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.