A polar vortex in the Earth's core.

MLA

Olson, Peter, and Jonathan Aurnou. “A Polar Vortex in the Earth’s Core.” Nature, vol. 402, no. 6758, Nov. 1999, p. 170. EBSCOhost, https://doi.org/10.1038/46017.

APA

Olson, P., & Aurnou, J. (1999). A polar vortex in the Earth’s core. Nature, 402(6758), 170. https://doi.org/10.1038/46017

Chicago

Olson, Peter, and Jonathan Aurnou. 1999. “A Polar Vortex in the Earth’s Core.” Nature 402 (6758): 170. doi:10.1038/46017.