Cita APA (7a ed.)

Sagan, D. (1990). Biospheres: Metamorphosis of planet earth. McGraw-Hill.

Cita Chicago Style (17a ed.)

Sagan, Dorin. Biospheres: Metamorphosis of Planet Earth. New York: McGraw-Hill, 1990.

Cita MLA (9a ed.)

Sagan, Dorin. Biospheres: Metamorphosis of Planet Earth. McGraw-Hill, 1990.