🌐EnglishEnglishDeutschEspañolFrançaisPortuguêsРусский한국어中文日本語EntityQ994401· pop 10· linked from 19 articlesfour-vertex theoremtheorem that every simple closed smooth curve in the plane has at least four points of locally extreme curvatureAvailable in 10 languagesEspañolFrançaisDeutsch中文РусскийPortuguêsSlovenianUkrainian한국어via Wikidata sitelinks · CC0ConnectionscurveEntitymaxima and minimaEntityCategoriesPolygonsTheorems about curvesTheorems in differential geometryTheorems in discrete geometry