00496nam a2200193 a 450000500170000002000180001708200150003510000240005024500550007426000320012930000240016149000340018550000190021960000080023863000200024663000240026685600060029085600060029620251219155950.0  a9783030380014  a515.7bBOR  aBorthwick, Davidd_  aSpectral theorybbasicsa concepts and applications  aswitzerlandbSpringerc2020  ax, 338p.c22cm.bHB  aGraduate texts in Mathematics  aincludes index  bc_  aSpectral theory  aFunctional analysis  f_  a_