books.google.com - This book is a unique introduction to the theory of linear operators on Hilbert space. The authors' goal is to present the basic facts of functional analysis in a form suitable for engineers, scientists, and applied mathematicians. Although the Definition-Theorem-Proof format of mathematics is used,...http://books.google.com/books/about/Linear_Operator_Theory_in_Engineering_an.html?id=t3SXs4-KrE0C&utm_source=gb-gplus-shareLinear Operator Theory in Engineering and Science