Worldwatch Institute, Brown, L. R., & Starke, L. (1999). State of the world, 1999: A Worldwatch Institute report on progress toward a sustainable society. Norton.
Lua i Stíl Chicago (17ú heag.)Worldwatch Institute, Lester Russell Brown, agus Linda Starke. State of the World, 1999: A Worldwatch Institute Report on Progress Toward a Sustainable Society. New York: Norton, 1999.
Lua MLA (9ú heag.)Worldwatch Institute, et al. State of the World, 1999: A Worldwatch Institute Report on Progress Toward a Sustainable Society. Norton, 1999.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.