Cita APA

Claybourne, A. (1999). The Usborne encyclopedia of planet earth. London: Usborne.

Chicago Style Citation

Claybourne, Anna. The Usborne Encyclopedia of Planet Earth. London: Usborne, 1999.

Cita MLA

Claybourne, Anna. The Usborne Encyclopedia of Planet Earth. London: Usborne, 1999.

Atenció: Aquestes cites poden no estar 100% correctes.