This excellent introduction to feedback control system design offers a theoretical approach that captures the essential issues and can be applied to a wide range of practical problems. 1992 edition.
For engineering students who have had an undergraduate course in signals and systems, including an introduction to frequency-domain methods of analyzing feedback control systems. The systems discussed are single input/single output and linear, operating in continuous time. Annotation c. Book News, Inc., Portland, OR (booknews.com)