Fix a prime number . Take the full subcategory of finitely generated abelian groups with no element of order . It is closed under finite direct sums and subgroups. If is the -primary torsion subgroup, the map is a reflection into this subcategory: every map to an allowed group kills . Therefore ordinary kernels in a category and reflected cokernels in a category supply all finite categorical limits and colimits. No nonzero finitely generated group has zero reflection, so the epimorphisms are precisely surjections and are all conormal epimorphisms. Multiplication by on is a monomorphism but not a normal monomorphism: its cokernel here is , whose kernel is , not . Multiplication by is normal; composing it with itself gives this nonnormal monomorphism.
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