Département de Mathématique, Université Libre de Bruxelles, Campus Plaine C.P. 218, Boulevard du Triomphe, 1050 Bruxelles, Belgium
Bibliografia
[1] G. Aronsson, Extension of functions satisfying Lipschitz conditions, Ark. Mat. 6 (1967), 551-561.
[2] G. Aronsson, On certain singular solutions of the partial differential equation $u^2_xu_xx+2u_xu_yu_xy+u^2_yu_yy=0$, Manuscripta Math. 47 (1984), 133-151.
[3] P. Baird and J. , Eells, A conservation law for harmonic maps, in: Geometry Symp. Utrecht 1980, Lecture Notes in Math. 894, Springer 1981, 1-25.
[4] M. Carpenter, The calculus of variations on a Riemannian manifold: regularity theory and the status of the Euler-Lagrange necessary condition, M.Sc. dissertation, Warwick 1991.
[5] D. M. Duc and J. Eells, Regularity of exponentially harmonic functions, Internat. J. Math., to appear.
[6] J. Eells and L. Lemaire, Selected topics in harmonic maps, CBMS Regional Conf. Ser. Math. 50, Amer. Math. Soc., 1983.
[7] J. Eells and L. Lemaire, Another report on harmonic maps, Bull. London Math. Soc. 20 (1988), 385-524.
[8] M. Giaquinta, Multiple Integrals in the Calculus of Variations and Non-linear Elliptic Theory, Ann. of Math. Stud. 105, Princeton Univ. Press 1983.
[9] C. Morrey, Multiple Integrals in the Calculus of Variations, Grundlehren Math. Wiss. 130, Springer, 1966.
[10] R. Schoen, Analytic aspects of the harmonic map problem, in: Math. Sci. Res. Inst. Publ. 2, Springer, 1984, 321-358.
[11] J. Serrin, The problem of Dirichlet for quasilinear elliptic differential equations with many independent variables, Philos. Trans. Roy. Soc. London A 264 (1969), 413-496.
[12] L. M. Sibner and R. J. Sibner, A non-linear Hodge-de Rham theorem, Acta Math. 125 (1970), 57-73.
[13] R. T. Smith, The second variation formula for harmonic mappings, Proc. Amer. Math. Soc. 47 (1975), 229-236.