Cita APA

Copi, I. M., & Cohen, C. (1999). Introduction to logic (9th ed.). Prentice Hall.

Chicago Edition Citation

Copi, Irving M., i Carl Cohen. Introduction to Logic. 9th ed. New Delhi: Prentice Hall, 1999.

Cita MLA

Copi, Irving M., i Carl Cohen. Introduction to Logic. 9th ed. Prentice Hall, 1999.