Petrilli, S., & Ponzio, A. Peirce and medieval semiotics: Susan Petrilli. Augusto Ponzio. Peirce's doctrine of signs : theory, applications, and connections.(1996).
Chicago-viite (17. p.)Petrilli, Susan, ja Augusto Ponzio. "Peirce and Medieval Semiotics: Susan Petrilli. Augusto Ponzio." Peirce's Doctrine of Signs : Theory, Applications, and Connections.(1996) .
MLA-viite (8. p.)Petrilli, Susan, ja Augusto Ponzio. "Peirce and Medieval Semiotics: Susan Petrilli. Augusto Ponzio." Peirce's Doctrine of Signs : Theory, Applications, and Connections.(1996), .
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