APA (7th ed.) Citation
Helmberg, G. (1969). Introduction to spectral theory in hilbert space. North-Holland Publishing Company.
Chicago Style (17th ed.) Citation
Helmberg, Gilbert. Introduction to Spectral Theory in Hilbert Space. Amsterdam: North-Holland Publishing Company, 1969.
MLA (9th ed.) Citation
Helmberg, Gilbert. Introduction to Spectral Theory in Hilbert Space. North-Holland Publishing Company, 1969.
Warning: These citations may not always be 100% accurate.