PERMAFROST — BLACK 299 



Prtor, W. T. 



*ll)47. Aerial surveylns on the Alaska Highway, 1942. Public Roads, vol. 24, 

 No. 11, pp. 275-290. 

 PtAtJP, H. M. 



1941. Botanical problera.s in Boreal America. Bot. Rev., vol. 7, pp. 147-248. 

 1947. The botany of southwestern Mackenzie. Sargentia 6. 



Richardson, H. W. 



1944. Construction in the tundra. Eng. News, vol. 132, pp. 956-961. 

 Richmond, Gerald M. 



1949. Stone nets, stone striijes, and soil stripes in the Wind River Mountains, 

 Wyoming. Journ. Geol., vol. 57, No. 2, pp. 143-153. 

 Rookie, W. A. 



1942. Pitting on Alaska farm lands : a new erosion problem. Geogr. Rev., 



vol. 32, pp. 128-134. 



SCH^VFER, J. P. 



1949. Some periglacial features in central Montana. Journ. Geol., vol. 57, 

 No. 2, pp. 154-174. 

 Shannon, "W. L., and Weij.s, W. A. 



1947. Tests for thermal diffusivity of granular materials. Presented at the 



50th annual meeting of the American Society for Testing Materials, 

 June 16-20. 

 Sharp, R. P. 



1942a. Ground-ice mounds in tundra. Geogr. Rev., vol. 32, No. 3, pp. 417- 



423. 

 *1942b. Soil structures in the St. Elias Range, Yukon Territory. Journ. 

 Geomorph., vol. 5, pp. 274-301. 

 Shelesnyak, M. C. 



1948. History of the Arctic Research Laboratory, Point Barrow, Alaska. 



Arctic, vol. 1, No. 2, pp. 97-106. 

 Smith, H. T. U. 



1949a. Periglacial features in the driftless area of southern Wisconsin. 



Journ. Geol., vol. 57, No. 2, pp. 196-215. 

 *1949b. Physical effects of Pleistocene climatic changes in nonglaciated 

 areas — eolian phenomena, frost action, and stream terracing. Bull. 

 Geol. Soc. Amer., vol. 00, pp. 1485-1516. 

 Smith, P. S. 



(Unpublished manuscript.) Permanent ground frost in Alaska. On file 

 with U. S. Geological Survey, Washington, D. C. 

 Smith, W. O. 



1939. Thermal conductivities in moist soils. Proc. Soil Sci. Soc. Amer., 



vol. 4, pp. 32-40. 

 1942. The thermal conductivity of dry soil. Soil Sci., vol. 53, No. 6, pp. 

 435^59. 

 Steche, H. 



*1933. Beitrage zur Frage der Strukturboden. Berichte Vorhandl. Sachsis- 

 chen Akad. Wiss. Leipzig, math.-phys. Kl., vol. 8, pp. 193-272. 

 Stone, Kirk. 



1948. Aerial photographic interpretation of natural vegetation in the 

 Anchorage area, Alaska. Geogr. Rev., vol. 38, No. 3, pp. 465, 474. 

 SUMGIN, M. I. 



*1947. Eternal ground frost in the U.S.S.R. 2d ed., rev, (not seen). 

 Vladivostok. 



