00813nam 2200229 450 00001663020050718115600.00-387-90666-520030918d1982----km-y0itay0103----baengUS<<A>> short introduction to perturbation theory for linear operatorsTosio KatoNew York [etc.]Springerc1982XIII, 161 p.25 cm.Operatori lineari515.7246(21. ed.)Analisi funzionale. Operatori lineari47A55General theory of linear operators. Perturbation theoryKato,Tosio40573ITUniversità della Basilicata - B.I.A.RICAunimarc000016630Short introduction to perturbation theory for linear operators34040UNIBAS