Here are the references for the papers in the November 30, 2001 issue of Science:

From the Reports section:

Detection of Molecular Hydrogen in the Atmosphere of Mars
Vladimir A. Krasnopolsky and Paul D. Feldman
Science Nov 30 2001: 1914-1917.
Abstract http://www.sciencemag.org/cgi/content/abstract/294/5548/1914

From the Perspectives section:

PLANETARY SCIENCE:
Clues to the Martian Atmosphere
Donald M. Hunten
Science Nov 30 2001: 1843-1844.
Summary http://www.sciencemag.org/cgi/content/summary/294/5548/1843

See also the NASA GSFC release at
http://www.gsfc.nasa.gov/topstory/20011129marswet.html

Also, there was another interesting paper released in Science Express last week (November 29, 2001):

Formation of Recent Martian Debris Flows by Melting of Near-Surface Ground Ice at High Obliquity
F. Costard, F. Forget, N. Mangold, and J. P. Peulvast
Published online November 29 2001; 10.1126/science.1066698 (Science
Express Reports)

Abstract

The observation of small gullies associated with recent surface run-off on Mars has renewed the question of liquid water stability at the surface of Mars. The gullies could be formed by groundwater seepage from underground aquifers, however, observations of gullies originating from isolated peaks and dune crests question this scenario. We show that these landforms may result from the melting of liquid water in the top few meters of the martian subsurface at high
obliquity. Our conclusions are based on the analogy between the martian gullies and terrestrial debris flows observed in Greenland and numerical simulations that show above-freezing temperatures can occur at high obliquities in the near-surface of Mars, and that such temperatures are only predicted at latitudes and for slope orientations corresponding to where the gullies have been observed on Mars.

Alex R. Blackwell
University of Hawaii