References
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- GIBSON , J. E. , 1903 , Nonlinear Automatic Control ( New York McGraw-Hill ).
- GREENFIELD , G. G. , and WARD , T. J. , 1968 , A.I.Ch.E. J., 14, 783; 1967 a, Industrial and Engineering Chemistry Fundamentals , 6 , 564 ; 1967 b, Ibid., 6, 571 .
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- †Communicated by the Authors.