Forand, Jean GuillaumeUyanik, Metin2026-07-132026-07-132017-11-29https://hdl.handle.net/10012/23730We provide two new proofs of the Bondareva-Shapley theorem, which states that the core of a transferable utility cooperative is nonempty if and only if the game is balanced. Both proofs exploit the fixed points of self-maps of the set of imputations, applying elementary existence arguments typically associated with noncooperative games to cooperative games.enPreprint