Cita APA (7a ed.)

Eco, U., & Marmo, C. (1989). On the Medieval theory of signs. J. Benjamin.

Cita Chicago Style (17a ed.)

Eco, Umberto, y Costantino Marmo. On the Medieval Theory of Signs. J. Benjamin, 1989.

Cita MLA (8a ed.)

Eco, Umberto, y Costantino Marmo. On the Medieval Theory of Signs. J. Benjamin, 1989.