Perturbation of the Eigenvalues of Quadratic Matrix Polynomials. - Heinz Langer; Branko Najman; Kresimir Veselic (SIAM J. Matrix Anal. Appl., 1992)

The Asymptotic Behavior of the Eigenvalues of a Singularly Perturbed Linear Pencil. - Branko Najman (SIAM J. Matrix Anal. Appl., 1998)