Linear Matrix Inequalities in System and Control Theory
Stephen Boyd
Control, 33:988–992, 1988. J. C. Willems. The Analysis of Feedback Systems, volume 62 of Research Monographs. MIT Press, 1969. J. C. Willems. Stability, instability, invertibility, and causality. SIAM J. Control, 7(4):645–671, November 1969.