@article{GDZPPN000461881,
title = {Invariant Measures and Orbit Closures for Unipotent Action on Homogeneous Spaces (Survey).},
journal = {Geometric and functional analysis},
volume = {4},
year = {1994},
pages = {236-258},
zbl = {0801.22008},
url = {http://dml.mathdoc.fr/item/GDZPPN000461881}
}
Ratner, M. Invariant Measures and Orbit Closures for Unipotent Action on Homogeneous Spaces (Survey).. Geometric and functional analysis, Tome 4 (1994) pp. 236-258. http://gdmltest.u-ga.fr/item/GDZPPN000461881/