G. K. Gilbert. Report on the Geology of the Henry Mountains, U. S. Geol. and Geogr. Surv. Ter., 1877, pp. 18-98.
Whitman Cross. The Laccolitic Mountain Groups of Colorado, Utah, and Arizona, 14th Ann. Rept. U. S. Geol. Surv., 1895, pp. 157-241, pls. 7-16.
W. H. Weed and L. V. Pirsson. Geology and Mineral Resources of the Judith Mountains of Montana, 18th Ann. Rept. U. S. Geol. Surv., Pt. iii, 1898, pp. 485-556, pl. 75.
W. H. Weed. Geology of the Little Belt Mountains, Montana, etc., 20th Ann. Rept. U. S. Geol. Surv., Pt. iii, 1900, pp. 387-400.
Vera de Derwies. Recherches géologiques et pétrographiques sur les loccolithes des environs de Piatigorsk (Caucase du Nord). Geneva, 1905, pp. 84, pls. 3.
R. A. Daly. The Mechanics of Igneous Intrusion, Am. Jour. Sci. (4), vol. 15, 1903, pp. 269-278; vol. 16, 1903, pp. 107-126.
Joseph Barrell. Geology of the Marysville Mining District, Montana. A study of Igneous Intrusion and Contact Metamorphism. Prof. Pap. 57, U. S. Geol. Surv., 1907, pp. 151-178.
Climatic condition in relation to land sculpture:—
C. E. Dutton. Tertiary History of the Grand Canyon District, Mon. 2, U. S. Geol. Surv., 1882, pp. 264, pls. 42.