General:—
Johannes Walther. Das Gesetz der Wüstenbildung in Gegenwart und Vorzeit. Berlin, 1900, pp. 175, many plates. (This extremely valuable work is now out of print, but both a revised edition and an English translation are promised for 1912.)
Siegfried Passarge. Die Kalihari. Berlin, 1904, pp. 662.
W. M. Davis. The Geographic Cycle in an Arid Climate, Jour. Geol., vol. 13, 1905, pp. 381-407.
Ellsworth Huntington. The Pulse of Asia. New York and Boston, 1907, pp. 415.
Sven Hedin. Scientific Results of a Journey through Central Asia, 1899-1900. Stockholm, 1904-1905, vols. 1 and 2, pp. 523 and 717, pls. 56 and 76.
Joseph Barrell. Relative Geological Importance of Continental, Littoral and Marine Sedimentation, Jour. Geol., vol. 14, 1906, pp. 316-356, 429-457, 524-568.
E. F. Gautier. Études sahariennes, Ann. de Géogr., vol. 16, 1907, pp. 46-69, 117-138.
The self-registering gauge of past climates:—
G. K. Gilbert. Lake Bonneville, Mon. I, U. S. Geol. Surv., Chapter vi, pp. 214-318.