Hess, KathrynLemaire, Jean-Michel2008-11-142008-11-142008-11-14199410.1016/0022-4049(94)90140-6https://infoscience.epfl.ch/handle/20.500.14299/30914WOS:A1994MT79000010Generalizing a definition of Lusternik and Schnirelmann to model categoriestext::journal::journal article::research article