1. T. K. Chu and H. W. Hendel, editors,Feedback and Dynamic Control of Plasmas(American Institute of Physics, New York, 1970).
2. Mathematical Description of Linear Dynamical Systems
3. J. M. Melcher, inFeedback and Dynamic Control of Plasmas, edited by T. K. Chu and H. W. Hendel (American Institute of Physics, New York, 1970), p. 38.