Given a matrix quadruple (A1,A2, A3,A4)epsilon F-n1 x n1 X F-n2 x n1 x F-n1
x n3 x F-n2 x n3 we completely characterize the feedback invariants of the
matrix pair
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for all possible selections of matrices X epsilon F-n1 x n2 and Y epsilon F
-n2 x n2 Inc. All rights reserved. (C) 1999 Elsevier Science.