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Perfect categories

Published online by Cambridge University Press:  20 January 2009

John Isbell
Affiliation:
State University of New York at Buffalo, Amherst, New York 14226
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This note extends to categories Fountain's theorem (2) that for a perfect monoid S, every flat S-set is projective. (The converse is known (4).)

Type
Research Article
Copyright
Copyright © Edinburgh Mathematical Society 1976

References

REFERENCES

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(4) Isbell, J. R., Perfect monoids, Semigroup Forum 2 (1971), 95118.CrossRefGoogle Scholar
(5) Mitchell, B., The dominion of Isbell, Trans. Amer. Math. Soc. 167 (1972), 319331.CrossRefGoogle Scholar
(6) Stenström, B., Flatness and localization over monoids, Math. Nachr. 48 (1971), 315334.CrossRefGoogle Scholar