APA (7th ed.) Citation

Eco, U., & Eco, U. (2007). On ugliness. Harvill Secker.

Chicago Style (17th ed.) Citation

Eco, Umberto, and Umberto;McEwen Eco. On Ugliness. Harvill Secker, 2007.

MLA (9th ed.) Citation

Eco, Umberto, and Umberto;McEwen Eco. On Ugliness. Harvill Secker, 2007.

Warning: These citations may not always be 100% accurate.