Cooley, W. F. (1912). The principles of science: A college text-book. Henry Holt.
Dyfyniad Arddull ChicagoCooley, William F. The Principles of Science: A College Text-book. New York: Henry Holt, 1912.
Dyfyniad MLACooley, William F. The Principles of Science: A College Text-book. Henry Holt, 1912.
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