Lyell, C. (1969). Principles of geology, being an attempt to explain the former: Changes of the earth's surface by reference to causes now in operation. Johnson Reprint Corp..
Chicago-viite (17. p.)Lyell, Charles. Principles of Geology, Being an Attempt to Explain the Former: Changes of the Earth's Surface by Reference to Causes Now in Operation. New York: Johnson Reprint Corp., 1969.
MLA-viite (9. p.)Lyell, Charles. Principles of Geology, Being an Attempt to Explain the Former: Changes of the Earth's Surface by Reference to Causes Now in Operation. Johnson Reprint Corp., 1969.
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