REFERENCES
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- HSU , C. C. , 1962 , A.I.E.E. Trans. , 81 , 165 .
- JONES , G. A. , and VAHOUNY , R. E. , 1965 , Control Engineering , 12 , 99 .
- TRUXAL , J. G. , 1955 , Control System Synthesis (Book) ( New York McGraw-Hill ).
- † Communicated by the Authors.