APA (7th ed.) Citation

Halmos, P. R. (1967). A Hilbert space problem book. Springer-Verlag.

Chicago Style (17th ed.) Citation

Halmos, Paul R. A Hilbert Space Problem Book. New York: Springer-Verlag, 1967.

MLA (8th ed.) Citation

Halmos, Paul R. A Hilbert Space Problem Book. Springer-Verlag, 1967.