BIBLIOGRAPHIC NOTE
<P>
After publication of  <I>On Computing the Complex Passivity Radius</I>
in CDC-ECC 2005, we discovered that we had overlooked two important
references
<UL>
<LI> T-S Hu and L Qiu, <B>Complex and Real Performance Radii and 
their Computation</B>, <I>International Journal of Robust and Nonlinear
Control</I> 7, p.187-209, 1997
<LI> T-S Hu and L Qiu, <B>On Structured Perturbation of Hermitian Matrices</B>,
<I>Linear Algebra Appl.</I> 275-276, pp.287-314, 1998.
</UL>
Many of the results in our paper first appeared in the references listed above.