REFERENCES
- BROCKETT , R. W. , 1966 , I.E.E.E. Trans, autom. Control , 11 , 596 .
- MARCUS , M. , and MINC , A. , 1964 , A Survey of Matrix Theory and Matrix Inequalities ( Allyn & Bacon ), p. 146 .
- ROSENBROCK , H. H. , 1963 , J. Electron. Control , 15 , 73 .
- SZEGO , G. P. , 1962 , J. Electron. Control , 13 , 69 .
- †Communicated by Dr. A. T. Fuller.