Campbell, Bruce A., Putzig, Nathaniel E., Carter, Lynn M., Morgan, Gareth A., Philips, Roger J., and Plaut, Jeffrey J. 2013. "
Roughness and near-surface density of Mars from SHARAD radar echoes."
Journal of Geophysical Research. E. Planets, 118, (3) 436–450.
https://doi.org/10.1002/jgre.20050.