Analysis of information sources in references of the Wikipedia article "Spectral theory" in English language version.
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: ISBN / Date incompatibility (help) and Arch W. Naylor, George R. Sell (2000). Linear Operator Theory in Engineering and Science; Vol. 40 of Applied mathematical science. Springer. p. 401. ISBN 0-387-95001-X., Steven Roman (2008). Advanced linear algebra (3rd ed.). Springer. ISBN 978-0-387-72828-5., I︠U︡riĭ Makarovich Berezanskiĭ (1968). Expansions in eigenfunctions of selfadjoint operators; Vol. 17 in Translations of mathematical monographs. American Mathematical Society. ISBN 0-8218-1567-9.{{cite book}}
: ISBN / Date incompatibility (help)