[7]L.N.Trefethen,Pseudospectra of matrices,in Numerical Analysis 1991,D.F.Griffiths and G.A.Watson,eds.,Longman Scientific and Technical,Harlow,UK,1992,pp.234-266. [8]L.N.Trefethen,Pseudospectra of linear operators,SIAM Rev.,39(1997),pp.383-406. [9]L.N.Trefethen,Spectra and pseudospectra:The behavior of non-normal matrices and opera- tors,in The Graduate Student's Guide to Numerical Analysis,M.Ainsworth,J.Levesley,and M.Marletta,eds.,Springer-Verlag,Berlin,1999,pp.217-250. [10]L.N.Trefethen,Computation of pesudospectra.In Acta numerical 1999,pp.247-295,Cambridge University Press,Cambridge [11]T.G.Wright and L.N.Trefethen,Computation of pseudospectra using ARPACK and eigs.SIAM J.Sci.Comput.,23(2001),pp.591-605 [12]T.G.Wright and L.N.Trefethen,Eigenvalues and pseudospectra of rectangular matrices Tech.report 01/13,Oxford University Computing Laboratory Numerical Analysis Group 8[7] L.N.Trefethen,Pseudospectra of matrices,in Numerical Analysis 1991,D.F.Griffiths and G.A.Watson,eds.,Longman Scientific and Technical,Harlow,UK,1992,pp.234-266. [8] L.N.Trefethen,Pseudospectra of linear operators,SIAM Rev.,39(1997),pp.383-406. [9] L.N.Trefethen,Spectra and pseudospectra:The behavior of non-normal matrices and opera￾tors,in The Graduate Student’s Guide to Numerical Analysis,M.Ainsworth,J.Levesley, and M.Marletta,eds.,Springer-Verlag,Berlin,1999,pp.217-250. [10] L.N.Trefethen,Computation of pesudospectra.In Acta numerical 1999,pp.247-295,Cambridge University Press,Cambridge [11] T.G.Wright and L.N.Trefethen,Computation of pseudospectra using ARPACK and eigs.SIAM J.Sci.Comput., 23(2001),pp.591-605 [12] T.G.Wright and L.N.Trefethen,Eigenvalues and pseudospectra of rectangular matrices ,Tech. report 01/13, Oxford University Computing Laboratory Numerical Analysis Group 8