ON ESSENTIAL SPECTRUM

[1] ON THE SPECTRAL THEORY OF ELLIPTIC DIFFERENTIAL OPERATORS .1. [J]. MATHEMATISCHE ANNALEN, 1961, 142 (01) : 22 - 130

[2] COBURN LA, 1966, MICH MATH J, V13, P285

[3] Gohberg I., 1957, AM MATH SOC TRANSL, V12, P43

[4] Gohberg I. C., 1957, USP MAT NAUK, V12, P43

[5] Goldberg S., 1966, UNBOUNDED LINEAR OPE

[6] GUSTAFSON K, TO BE PUBLISHED

[7] ON OPERATORS WHOSE FREDHOLM SET IS COMPLEX PLANE [J]. PACIFIC JOURNAL OF MATHEMATICS, 1967, 21 (02) : 275 - &

[8] Kato T., 1966, PERTURBATION THEORY, V132, P396

[9] NEUMANN JV, 1935, ACTUALITES SCI IND, V229

[10] NEUMANN JV, 1932, ANN MATH, V33, P294

[1] ON THE SPECTRAL THEORY OF ELLIPTIC DIFFERENTIAL OPERATORS .1. [J]. MATHEMATISCHE ANNALEN, 1961, 142 (01) : 22 - 130

[2] COBURN LA, 1966, MICH MATH J, V13, P285

[3] Gohberg I., 1957, AM MATH SOC TRANSL, V12, P43

[4] Gohberg I. C., 1957, USP MAT NAUK, V12, P43

[5] Goldberg S., 1966, UNBOUNDED LINEAR OPE

[6] GUSTAFSON K, TO BE PUBLISHED

[7] ON OPERATORS WHOSE FREDHOLM SET IS COMPLEX PLANE [J]. PACIFIC JOURNAL OF MATHEMATICS, 1967, 21 (02) : 275 - &

[8] Kato T., 1966, PERTURBATION THEORY, V132, P396

[9] NEUMANN JV, 1935, ACTUALITES SCI IND, V229

[10] NEUMANN JV, 1932, ANN MATH, V33, P294