Finite element methods for the solution of problems with rough input data.- Treatment of a re-entrant vertex in a three-dimensional poisson problem.- On the approximation of linear elliptic systems on polygonal domains.- The regularity of interface-problems on corner-regions.- Spectral analysis of singular Sturm-Liouville problems with operator coefficients.- On a numerical method for fracture mechanics.- On finite element methods for nonlinear elliptic problems on domains with corners.- Singularities in elliptic problems.- Boundary integral equations for sound radiation by a harmonically vibrating baffled plate.- Eigenfunction expansions for non self adjoint operators and separation of variables.- Castigliano and sobolev.- An integral equation formulation for a boundary value problem of elasticity in the domain exterior to an arc.- Scalar decomposition of elastic waves scattered by planar cracks.- Boundary element methods for singularity problems in fracture mechanics.- Sur l'approximation des solutions du probleme de Dirichlet dans un ouvert avec coins.- The treatment of singularities in orthonormalization methods for numerical conformal mapping.- Calculation of potential in a sector.- Singularities of cracks with generalized finite elements.- The practical treatment of stress concentrations and singularities within finite element displacement algorithms.- Series expansions of biharmonic functions around a slit.- Invariance properties and special structures near conical boundary points.- A comparison of the local behavior of spline L2-projections, fourier series and legendre series.