The theorem was proved by Stefan Banach in his 1932 Théorie des opérations linéaires.
Stefan Edberg | Stefan Sagmeister | Stefan Lazarević | Stefan Zweig | Stefan Raab | Stefan Heym | Ştefan Voitec | Stefan Dennis | Stefan Żeromski | Stefan Wyszyński | Stefan Nemanja | Stefan Karlsson | Stefan Brockhoff | Stefan Aust | Banach space | Adam Stefan Sapieha | Stefan Weisman | Ştefan Vodă | Stefan Skarbek | Stefan Simonsson | Stefan Olsson | Stefan Lorant | Stefan Lochner | Stefan Heidemann | Stefan Guzy | Stefan Gryff | Stefan Grossman | Stefan Everts | Stefan Danailov | Hahn–Banach theorem |