🌐EnglishEnglishDeutschEspañolFrançaisItalianoNederlandsPolskiPortuguêsSvenskaРусскийالعربية한국어中文日本語EntityQ315296· pop 22· linked from 82 articlesErlangen programresearch program on the symmetries of geometryAvailable in 22 languagesEspañolFrançaisDeutsch中文日本語РусскийPortuguêsItalianoالعربيةCatalanConnectionsEuclidean geometryEntitynon-Euclidean geometryEntityCategoriesClassical geometryErlangenGroup theoryHomogeneous spacesSymmetry