This up-to-date introductory treatment employs category theory to explore the theory of structures. Its unique approach stresses concrete categories and present

Because her good luck cat Woogie has already used up eight of his nine lives in narrow escapes from disaster, a Native American girl worries when he disappears.

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Awaiting the birth of his first kittens, feline P. I. Joe Grey, his companion Dulcie, and their furry sleuthing pals must unmask a killer preying on some of the

This volume contains the articles contributed to the Conference on Categorical Algebra, held June 7-12,1965, at the San Diego campus of the University of Califo