%0 Journal Article
%A Sols Lucía, Ignacio
%A Giraldo Suárez, Luis
%T The irregularity of ruled surfaces in P 3
%D 1998
%@ 0010-0757
%U https://hdl.handle.net/20.500.14352/58402
%X In this paper the authors determine which pairs of integers (d,q)  appear as the degree and the irregularity of a ruled surface S  in P 3  . The proof is based on the study of the base   curve C  of S  in the  Grassmannian G(1,3) ⊂P 5  : according   to  the dimension of the  span of  C   some inequalities on d,q  are given, and the existence of a curve  C  satisfying them follows from previous results of Rathmann  and Pasarescu  on curves in P 4   and in  P 5  .
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