Citazione Stile APA (7a Edizione)

Discovery Channel School. (2005). History of the earth (version 2.0.). Discovery Channel School.

Citazione stile Chigago Style (17a edizione)

Discovery Channel School. History of the Earth. version 2.0. s.l: Discovery Channel School, 2005.

Citatione MLA (9a ed.)

Discovery Channel School. History of the Earth. version 2.0. Discovery Channel School, 2005.