From the January 20, 2006, issue of Science:

Formation of Glaciers on Mars by Atmospheric Precipitation at High Obliquity
F. Forget, R. M. Haberle, F. Montmessin, B. Levrard, and J. W. Head
Science 311, 368-371 (2006)
Abstract
Supporting Online Material

Note: The online embargo warning may pop up until the links go active in a short while. However, the official embargo has been lifted as witnessed by the press releases below.

See also:
Martian snow source of tropical glaciers, research team reports
Snow on Mars Created Glaciers Near Equator

Another related paper was just published in the January 31, 2006, issue of Earth and Planetary Science Letters:

Extensive valley glacier deposits in the northern mid-latitudes of Mars: Evidence for Late Amazonian obliquity-driven climate change
J.W. Head, D.R. Marchant, M.C. Agnew, C.I. Fassett and M.A. Kreslavsky
Earth Planet. Sci. Lett. 241, 663-671 (2006)
Abstract

A 5.72 Mb PDF preprint is available from the Brown University Planetary Geosciences Group website.

For those without online access to Science, a reprint (~376 Kb PDF) is available. Also, though I might be mistaken, I believe the Supporting Online Material for papers is open to non-subscribers.