Παραπομπή APA

Gelca, R., & Andreescu, T. (2007). Putnam and beyond. Springer.

Παραπομπή Chicago Style

Gelca, Razvan, και Titu Andreescu. Putnam and Beyond. New York: Springer, 2007.

Παραπομπή MLA

Gelca, Razvan, και Titu Andreescu. Putnam and Beyond. Springer, 2007.