Παραπομπή σε μορφή APA (7η εκδ.)

Heal, G. M. (1998). Valuing the future: Economic theory and sustainability. Columbia University Press.

Παραπομπή σε μορφή Chicago (17η εκδ.)

Heal, G. M. Valuing the Future: Economic Theory and Sustainability. New York: Columbia University Press, 1998.

Παραπομπή σε μορφή MLA (9th εκδ.)

Heal, G. M. Valuing the Future: Economic Theory and Sustainability. Columbia University Press, 1998.