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Schrödinger operators, with applications to quantum mechanics and global geometry. Cycon, H. L. (Hans Ludwig), 1942-, Simon, Barry, 1946-, Beiglböck, E., 1939-. Berlin: Springer-Verlag. 1987. ISBN978-0387167589. OCLC13793017.{{cite book}}: CS1 maint: others (link)