Liberati, A. M., Bourbon, F., Ancient Rome: history of a civilization that ruled the world, Vercelli, Edizioni White star, 2001, (Le grandi civiltà).

Rome's greatness grew out of its imperial program of conquering others and establishing colonies. This military expansion at once brought great material benefit to the Roman state and guaranteed a pipeline of wealth for Rome, the imperial city. And Rome becomes a cosmopolitan capital. The Ancient Romans borrowed much of their art from the Greeks, yet they did develop their own unique style. White Star Publisher