@article{Varney2011a,
author = "R. H. Varney and M. C. Kelley and M. J. Nicolls and C. J. Heinselman and R. L. Collins",
title = "The electron density dependence of polar mesospheric summer echoes",
year = 2011 ,
journal = "J Atmos Sol-Terr Phy",
volume = 73,
keywords = "amisr, pfisr",
doi = "10.1016/j.jastp.2010.07.020"
}