Citazione Stile APA (7a Edizione)

Posen, M. (2003). Question and Answer Encyclopedia: The natural World. Parragon Publishing.

Citazione stile Chigago Style (17a edizione)

Posen, Michael. Question and Answer Encyclopedia: The Natural World. Bath Bai IHE, Inglaterra: Parragon Publishing, 2003.

Citatione MLA (9a ed.)

Posen, Michael. Question and Answer Encyclopedia: The Natural World. Parragon Publishing, 2003.