The Poincaré-Cartan invariant in the calculus of variations. (English) Zbl 0303.53040

Symp. math. 14, Geom. simplett. Fis. mat., Teor. geom. Integr. Var. minim., Convegni 1973, 219-246 (1974).


53C15 General geometric structures on manifolds (almost complex, almost product structures, etc.)
49J10 Existence theories for free problems in two or more independent variables
74A99 Generalities, axiomatics, foundations of continuum mechanics of solids