APA način citiranja

Herrera León, L., & Martínez Barreiro, L. A. (2009). The multiple pregnancy: Is it really a factor of high obstetric risk?

Čikaški stil citiranja

Herrera León, Lorenzo, i Luis Armando Martínez Barreiro. The Multiple Pregnancy: Is It Really a Factor of High Obstetric Risk? 2009.

MLA način citiranja

Herrera León, Lorenzo, i Luis Armando Martínez Barreiro. The Multiple Pregnancy: Is It Really a Factor of High Obstetric Risk? 2009.