Halmos, Paul R. <br/><br/>
Introduction to Hilbert Space and the Theory of Spectral Multiplicity / 
Paul R. Halmos. 
 - 2nd ed. 
 - New York :  Dover Publications,  ©2017. 
 - 114 p. : 
 - Dover Books in Science and Mathematics .
<br/><br/> Originally published: New York : Chelsea Publishing Company, 1957. 
<br/><br/><label>ISBN: </label>9780486817330 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Spectral theory (Mathematics)<br/>Hilbert space.
<br/><br/><label>Dewey Class. No.: </label>515.733  / HAL/I