'(sE-A)Z1 = |------------------------|------------|.   (1)
                   |            O           | sE(r)-A(r) |

  The pencil sE(eps,inf)-A(eps,inf) is in staircase form, and it
  contains all Kronecker column indices and infinite elementary
  divisors of the pencil sE-A. The pencil sE(r)-A(r) contains all
  Kronecker row indices and elementary divisors of sE-A.
  Note: X is a pencil.

  If MODE = 'T', then the submatrices having full row and column
  rank in the pencil sE(eps,inf)-A(eps,inf) in (1) a