The algebras of operators arise frequently in the study of representations of Lie groups, both finite-dimensional and infinite-dimensional. This survey begins with extensive background material and advances to considerations of the algebras of operators in Hilbert space and covariant representations and connections. 1988 edition. Reprint of the North-Holland, Amsterdam and New York, 1988 edition.
Here's a sample of other books in this Dover category
Quantum Mechanics by Albert Messiah Subjects include formalism and its interpretation, analysis of simple systems, symmetries and invariance, methods of approximation, elements of relativistic quantum mechanics, much more. "Strongly recommended." — American Journal of Physics.
Linear Operators for Quantum Mechanics by Thomas F. Jordan Suitable for advanced undergraduates and graduate students, this compact treatment examines linear space, functionals, and operators; diagonalizing operators; operator algebras; and equations of motion. 1969 edition.
Theory of Linear Operations by Stefan Banach, F. Jellett Written by the founder of functional analysis, this is the first text on linear operator theory. Additional topics include the calculus of variations and theory of integral equations. 1987 edition.