APA استشهاد

Reitner, J., & Keupp, H. (1991). Fossil and recent sponges. Springer.

استشهاد بنمط شيكاغو

Reitner, J., و H. Keupp. Fossil and Recent Sponges. New York: Springer, 1991.

MLA استشهاد

Reitner, J., و H. Keupp. Fossil and Recent Sponges. Springer, 1991.