On threefolds covered by lines
نویسندگان
چکیده
منابع مشابه
On Quadrisecant Lines of Threefolds in P
The classical theorem of general projection for surfaces says that a general projection in P of a smooth complex projective surface S of P is a surface F with ordinary singularities i.e. its singular locus is either empty or is a curve γ such that (i) γ is either non singular or has at most a finite number of ordinary triple points; (ii) every smooth point of γ is either a nodal point or a pinc...
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ژورنال
عنوان ژورنال: Abhandlungen aus dem Mathematischen Seminar der Universität Hamburg
سال: 2000
ISSN: 0025-5858,1865-8784
DOI: 10.1007/bf02940914