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2. Babuška, I., Dorr, M. R., Error Estimates for the Combined h and p-version of the Finite Element Method, Numer. Math 37 (1981), 257–277.
3. Babuška, I., Guo, B., Regularity of the solution of elliptic problems with precise analytic data. Part I: Boundary value problem for linear elliptic equations of second order. Tech. Note BN-1047, IPSTUM 1986.
4. Babuška, I. Guo, B., The h-p Version of the Finite Element Method for Domains with Curved Boundaries, To appear in SIAM J. Numer. Anal., 1987 (Tech. Note BN-1057, IPSTUM 1987 ).
5. Babuška, I,, Guo, B., The h-p version of the finite element method for problems with non- homogenous essential boundary conditions. To appear.