Schur Complements on Hilbert Spaces and Saddle Point Systems, Journal of Computational and Applied Mathematics, Volume 225, Issue 2, 2009, pp 581-593.

Subspace interpolation with applications to elliptic regularity, Numerical Functional Analysis and Optimization, Volume 29, Issue 1&2, 2008, pp 88-114.

Improving the rate of convergence of `high order finite elements' on polyhedra II: Mesh Refinements and Interpolation, with V.~Nistor and L.~Zikatanov, Numerical Functional Analysis and Optimization, Vol. 28, No 7-8, 2007, pp. 775-824.

A Unified Approach for Uzawa Algorithms, SIAM Journal of Numerical Analysis, Volume 44, Issue 6, 2006, pp. 2633-2649

Partition of Unity Finite Element Method Implementation for Poisson Equation, with J. Sun, Advances in Applied and Computational Mathematics, Nova Publishers, 2006, pp. 35-46

Improving the rate of convergence of `high order finite elements' on polyhedra I: apriori estimates, with V.~Nistor and L.~Zikatanov, Numerical Functional Analysis and Optimization, Vol. 26, No 6, 2005, pp. 613-639.

Improving the rate of convergence of `high order finite elements' on polygons and domains with cusps, with V. Nistor and L. Zikatanov, Numerische Mathematik, Vol. 100, No 2, 2005, pp. 165 -184

Partition of unity method on non-matching grids for the Stokes problem, with J.~Chen, Y.~Huang, J.~Xu and L.T.~Zikatanov, Journal of Numerical Mathematics, Vol.13, No.3, 2005, pp.157-169.

Regularity estimates for elliptic boundary value problems in Besov spaces, with J. H. Bramble and Jinchao Xu, Mathematics of Computation, 72 (2003), 1577-1595.

Regularity estimates for elliptic boundary value problems with smooth data on polygonal domains, with J. H. Bramble and Jinchao Xu, Jornal of Numerical Mathematics, Vol.11, No.2, 2003, pp.75-177.

Regularity estimates for solutions of the equations of linear elasticity in convex plane polygonal domains with J. H. Bramble, Z. angew. Math. Phys.(ZAMP), 54(2003), 874-878.

Using finite element tools in proving shift theorems for elliptic boundary value problems, with J.H. Bramble, and J.E. Pasciak, Numerical Linear Algebra with Application, Volume 10, Issue no 1-2, 33-64, 2003.

New Interpolation Results and Applications to Finite Element Methods for Elliptic Boundary Value Problems, with J. H. Bramble and J. Pasciak. East-West J. Numer. Math. Vol.9, No.3, 2001, pp. 1-20.

Shift theorems for the biharmonic Dirichlet problem, with J. H. Bramble and J. Pasciak, Recent Progress in Computational and Applied PDEs by Kluwer Academic/Plenum Publishers, volume of proceedings for the CAPDE conference held in Zhangjiajie, China, July 2001.

Boundary value problems and regularity on polyhedral domains, with V.~Nistor and L.~Zikatanov, IMA Preprint Series # 1984, August 20, 2004.

Regularity and well posedness for the Laplace operator on polyhedral domains, with V.~Nistor and L.~Zikatanov, Cornell University Library, arXiv.org database, October 7, 2004.

Partition of Unity Method for Stokes Problem on Nonmatching Grids, with Jinchao Xu, Proceedings of the 2003 Copper Mountain Conference on Multigrid Methods.

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