APA استشهاد

Beck, W. (1991). Life: An introduction to biology/3rd ed (3rd ed.). Harper Collins Publishers.

استشهاد بنمط شيكاغو

Beck, William. Life: An Introduction to Biology/3rd Ed. 3rd ed. Harcard: Harper Collins Publishers, 1991.

MLA استشهاد

Beck, William. Life: An Introduction to Biology/3rd Ed. 3rd ed. Harper Collins Publishers, 1991.