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Non-reflexive curves
Abramo Hefez, Non-reflexive curves, Compositio Mathematica 69 (1) (1989), 3–35. The edition read is the journal scan at the Numdam article record, obtained from its PDF endpoint.
Section 2 recalls the conormal projection, reflexivity and the Segre–Wallace separability criterion. Its generic order of contact statement (2.1) is cited to earlier work of Hefez and Kleiman. For a nonlinear irreducible projective curve over an algebraically closed field of characteristic , the consequence at the top of printed p. 5 excludes non-reflexivity when its degree is less than .
Read status: claims checked; original proof unread. The introduction and the preliminary discussion on printed pp. 3–5 were read from the scan's text. The degree consequence and its placement were checked on the image of printed p. 5. The cited original proof of (2.1), the separability criterion and the later sections were not verified.
Bears on. The degree-versus-characteristic condition is a source interface in the curve obstruction relevant to Problem 1159, as used in Asgarli–Ghioca–Yip's curve argument. The componentwise and union hypotheses must also be matched to Entin's reflexivity interface. This source gives no approximation theorem for arbitrary blocking sets.
The scan's cover carries a 1989 all-rights-reserved notice of the Foundation Compositio Mathematica; the first article page also names Kluwer Academic Publishers. These notices and Numdam's reuse terms were read on 2026-10-17. The archive's permission to distribute on its own servers does not grant redistribution elsewhere. No file of this source is held because no license on record permits redistribution.