Projective manifolds with hyperplane sections being four-sheeted covers of projective space
نویسندگان
چکیده
منابع مشابه
Quasi-projective covers of right $S$-acts
In this paper $S$ is a monoid with a left zero and $A_S$ (or $A$) is a unitary right $S$-act. It is shown that a monoid $S$ is right perfect (semiperfect) if and only if every (finitely generated) strongly flat right $S$-act is quasi-projective. Also it is shown that if every right $S$-act has a unique zero element, then the existence of a quasi-projective cover for each right act implies that ...
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ژورنال
عنوان ژورنال: Proceedings of the Japan Academy, Series A, Mathematical Sciences
سال: 2006
ISSN: 0386-2194
DOI: 10.3792/pjaa.82.8