Morash, Ronald P. Bridge to abstract mathematics : mathematical proof and structures / Ronald P. Morash. - 2nd ed. - New York : McGraw-Hill, c1991. - xviii, 389 p. : ill. ; 24 cm. Includes index. ISBN: 0070430438 Subjects--Topical Terms: Logic, Symbolic and mathematical.Mathematics. LC Class. No.: QA9 / .M74 1991