Abstract
Our aim is to analyze and to publicize two interesting properties — well known in universal algebra for varieties — that a regular category, and in particular an exact category, may possess: theMaltsev property, asserting the permutabilitySR=RS of equivalence relations on any object, and the weakerGoursat property, asserting only thatSRS=RSR. We investigate these properties, give various equivalent forms of them, and develop some of their useful consequences.
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Carboni, A., Kelly, G.M. & Pedicchio, M.C. Some remarks on Maltsev and Goursat categories. Appl Categor Struct 1, 385–421 (1993). https://doi.org/10.1007/BF00872942
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DOI: https://doi.org/10.1007/BF00872942