Perry, J. S. (1996). Understanding our planet: An overview of the major scientific activities of ICSU and its partners that address global environmental change (Second edition.). International Council of Scientific Unions.
Lua i Stíl Chicago (17ú heag.)Perry, John S. Understanding Our Planet: An Overview of the Major Scientific Activities of ICSU and Its Partners That Address Global Environmental Change. Second edition. Paris, France: International Council of Scientific Unions, 1996.
Lua MLA (9ú heag.)Perry, John S. Understanding Our Planet: An Overview of the Major Scientific Activities of ICSU and Its Partners That Address Global Environmental Change. Second edition. International Council of Scientific Unions, 1996.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.