@article{Themens2014a, author = "D. Themens and P. Jayachandran and M. J. Nicolls and J. W. MacDougall", title = "A Top to Bottom Evaluation of IRI-2007 within the Polar Cap", year = 2014 , journal = "J. Geophys. Res.", volume = 119, keywords = "amisr, risrn", doi = "10.1002/2014JA020052" }