James Hutton (1788*). “Theory of the earth; or an investigation of the laws observable in the composition, dissolution and restoration of land upon the globe. (From. the Trans., Roy. soc. of Edinb.).”, p.86
David Hume (1874). “A Treatise on Human Nature: Being an Attempt to Introduce the Experimental Method of Reasoning Into Moral Subjects; and Dialogues Concerning Natural Religion”, p.306