[1] Yershov E D. General Geocryology[M]. Cambridge: Cambridge University Press, 1998. 580. [2] Pemafrost Subcommittee. Glossary of permafkost and Related Ground-Ice Terms[R]. Associate Committee on Geotechnical Research, National Research Council of Canada, Technical Memorandum No.142, 1988. 156. [3] Brown J, Ferriana Jr O J, Heginbottom J A, Melnikov, et al. Digital Circum-Arctic Map of Permafrost and Ground-Ice Conditions[A]. International Permafrost Association, Data and Infomation Working Group, comp. Circumpolar Active-Layer Permafrost System (CAPS), version 1.0[C]. CD-ROM available fkom the National Snow and Ice Data Center, nside@kryos.colorado. edu NSIDC, University of Colorado, Boulder, CO 80303-0449, 1997, USA. [4] Zhang T, Barry R G, Knowles K, et al. Statistics and characteristics of pernafrost and ground-ice distribution in the Northern Hemisphere[J]. Polar Geography, 1998, 23(2): 132-154. [5] Zhang T, Armstrong R L, Barry R G, et al. Seasonal freeze/thaw cycles in the Northern Hemisphere[R]. Supplement to EOS, Transactions, American Geophysical Union, 2000, 81(48), November 28. |