On the category of comodules over corings
نویسنده
چکیده
It is well known that the category MC of right comodules over an A-coring C, A an associative ring, is a subcategory of the category of left modules ∗CM over the dual ring ∗C. The main purpose of this note is to show that MC is a full subcatgeory in ∗CM if and only if C is locally projective as a left A-module.
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