Childs, Lindsay N. A concrete introduction to higher algebra [electronic resource] / by Lindsay N. Childs. - 3rd ed. - New York, NY : Springer New York, 2009. - xiv, 603 p. : digital ; 24 cm. - Undergraduate texts in mathematics, 0172-6056 . ISBN: 9780387747255 (electronic bk.) 9780387745275 (paper) Subjects--Topical Terms: Number theory.Number theory--Problems, exercises, etc.Algebra.Mathematics. LC Class. No.: QA155 / .C53 2009 Dewey Class. No.: 512.74