1. Effects of global warming on permafrost and active-layer thickness: results from transient general circulation models;Anisimov;Global and Planetary Change,1997
2. Anonymous, 1999. Frozen woolly mammoth inspires cloning project. The New York Times, October 5, late edition, F5.
3. Auerbach, N.A., Walker, D.A., Bockheim, J., 1997. Landcover of the Kuparuk River Basin, Alaska. Tundra Ecosystem Analysis and Mapping Laboratory, University of Colorado, Boulder, 1:250,000.
4. On the ground ice or frozen soil of Siberia;Baer;Journal of the Royal Geographical Society,1838
5. A Decade of Reform in Geographic Education: Inventory and Prospect,1994