Copi,Irving M Cohen, & Carl & Rodych,Victor. (2020). Introduction to logic (15.). Routledge.

Copi,Irving M Cohen, and Carl & Rodych,Victor. Introduction to Logic. 15. New York: Routledge, 2020.

Copi,Irving M Cohen, and Carl & Rodych,Victor. Introduction to Logic. 15. Routledge, 2020.