APA استشهاد

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

استشهاد بنمط شيكاغو

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

MLA استشهاد

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