Eco, U., Lambertini, R., Marmo, C., & Tabarroni, A. On animal language in the medieval classification of signs: Umberto Eco. Roberto Lambertini. On the Medieval theory of signs.(1989).
Chicago-referens (17:e uppl.)Eco, Umberto, Roberto Lambertini, Costantino Marmo, och Andrea Tabarroni. "On Animal Language in the Medieval Classification of Signs: Umberto Eco. Roberto Lambertini." On the Medieval Theory of Signs.(1989) .
MLA-referens (8:e uppl.)Eco, Umberto, et al. "On Animal Language in the Medieval Classification of Signs: Umberto Eco. Roberto Lambertini." On the Medieval Theory of Signs.(1989), .
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