We prove that pure morphisms of commutative rings are effective $A$-descent morphisms where $A$ is a (COMMUTATIVE RINGS)$^op$-indexed category given by (i) finitely generated modules, or (ii) flat modules, or (iii) finitely generated flat modules, or (iv) finitely generated projective modules.
Keywords: Indexed categories, effective descent morphisms, pure morphisms.
2000 MSC: 13B02, 13B99, 18A20, 18A22, 18D30.
Theory and Applications of Categories, Vol. 10, 2002, No. 9, pp 180-186.
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