Sub-freezing activity of microorganisms and the potential habitability of Mars’ polar regions. Jakosky BM, Nealson KH, Bakermans C, Ley RE and Mellon MT. Astrobiology. 3:343-350. (2003). DOI: https://doi.org/10.1089/153110703769016433
Complexity in natural microbial ecosystems: the Guerrero Negro experience. Spear JS, Ley RE, Berger AB and Pace NR. Biological Bulletin. 204:168-173. (2003). DOI: https://doi.org/10.2307/1543553