We use a projective transformation method of Tóth and Valtr to show that a certain number of points in general position in the plane contain the vertex set of a convex \documentclass[12pt]{minimal}
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\begin{document}$$n$$\end{document}-gon if their convex hull is an \documentclass[12pt]{minimal}
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\begin{document}$$(n\!-\!1)$$\end{document}-gon.