Approximation of eigenvalues of differential equations with non-smooth coefficients Uday Banerjee — 1988 ESAIM: Mathematical Modelling and Numerical Analysis - Modélisation Mathématique et Analyse Numérique
A note on the effect of numerical quadrature in finite element eigenvalue approximation. Uday Banerjee — 1992 Numerische Mathematik
Estimation of the Effect of Numerical Integration in Finite Element Eigenvalue Approximation. Uday Banerjee; John E. Osborn Numerische Mathematik