000 002640000a22001090004500
041 _aENG
080 _aB313N08 L3
082 _aB313N08 L3
100 _aFRIEDRICHS (Kurt Otto)
245 _aSpectral theory of operators in Hilbert space
650 _aHILBERT SPACE
999 _c252960
_d252960