Purtill, R. L. (1979). Logic: Argument, refutation, and proof. Harper & Row Publishers Inc.
Chicago Style (17th ed.) CitationPurtill, Richard L. Logic: Argument, Refutation, and Proof. Harper & Row Publishers Inc, 1979.
MLA (8th ed.) CitationPurtill, Richard L. Logic: Argument, Refutation, and Proof. Harper & Row Publishers Inc, 1979.
Warning: These citations may not always be 100% accurate.