Citazione Stile APA (7a Edizione)

Porter, J., & Punnett, N. (1989). Physical environment and human activities. Oxford Univ. Press.

Citazione stile Chigago Style (17a edizione)

Porter, John, e Neil Punnett. Physical Environment and Human Activities. Oxford: Oxford Univ. Press, 1989.

Citatione MLA (9a ed.)

Porter, John, e Neil Punnett. Physical Environment and Human Activities. Oxford Univ. Press, 1989.