The Birkhoff–Kellogg theorem and its generalizations by Schauder and Leray have applications to partial differential differential equations.
Jean-Paul Sartre | Jean-Jacques Rousseau | Jean Cocteau | Jean Genet | Jean-Luc Godard | Wyclef Jean | Jean Racine | Jean Chrétien | Jean Michel Jarre | Jean Paul Gaultier | Jean Nouvel | Jean-Michel Basquiat | Jean Giraud | Jean Sibelius | Jean-Luc Ponty | Jean-Baptiste-Camille Corot | Jean-Claude Van Damme | Jean Renoir | Jean-Pierre Rampal | Jean-Léon Gérôme | Jean Harlow | Jean Anouilh | Billie Jean King | Jean Giraudoux | Jean-Bertrand Aristide | Jean Baudrillard | Jean-Pierre Thiollet | Jean-Martin Charcot | Jean Gabin | Jean de Florette |
One of the most popular activities were the lectures at the Université en Captivité, headed by Lieutenant Jean Leray, formerly a mathematics professor at the Université de Nancy.