Home›Systems of set theory›Zermelo set theory🌐EnglishEnglishDeutschFrançaisItalianoNederlandsPortuguês한국어中文日本語EntityQ191853· pop 11· linked from 163 articlesZermelo set theorysystem of set theory (in mathematics)Available in 11 languagesFrançaisDeutsch中文日本語PortuguêsItalianoEstonianNederlandsPiedmonteseUkrainianConnectionsRussell's paradoxEntityordinal numberEntityCategoriesSystems of set theory