🌐EnglishEnglishDeutschTiếng ViệtTürkçeРусский中文日本語EntityQ15895894· pop 9· linked from 6 articlesFinsler–Hadwiger theoremdescribes a third square derived from any two squares that share a vertexAvailable in 8 languagesDeutsch中文日本語РусскийTamilTiếng ViệtTürkçevia Wikidata sitelinks · CC0ConnectionsInternational Standard Book NumberEntitysquareEntityCategoriesEuclidean geometryTheorems about quadrilaterals