Beer, J. (2017). Penguins vs. Puffins. National Geographic Kids.
Cita Chicago Style (17a ed.)Beer, Julie. Penguins Vs. Puffins. Washington, D.C.: National Geographic Kids, 2017.
Cita MLA (8a ed.)Beer, Julie. Penguins Vs. Puffins. National Geographic Kids, 2017.
Precaución: Estas citas no son 100% exactas.