Heiken, G., Funiciello, R., & De Rita, D. (2005). The seven hills of Rome: A geological tour of the eternal city. Princeton University Press.

Heiken, Grant, R. Funiciello, and Donatella De Rita. The Seven Hills of Rome: A Geological Tour of the Eternal City. Princeton: Princeton University Press, 2005.

Heiken, Grant, et al. The Seven Hills of Rome: A Geological Tour of the Eternal City. Princeton University Press, 2005.