references for the spectral theorem

Question

Recently, I am thinking about the question in spectral theory. And I finally found that I need help with the properties of unitary operator. Its a consequence of the spectral theorem for the normal operator, as the wiki says. The spectral theorem in the book I have ever read is only for self-adjoint operator and without many details.

Could anybody here recommend me some references for this theorem?

Answer 1

Reed and Simon, Methods of Modern Mathematical Physics, Volume 1, Chapter 8.

Answer 2

Rudin, "Functional Analysis", chapter 12

Answer 3

Conway, Functional Analysis, Chapter IX.

Pedersen, Analysis NOW, Section 4.4 & 4.5.

Lang, Real and Functional Analysis, Chapters XVIII, XIX, XX (yes this is a long book!).