The location of zeros of polynomials

Let A be a complex n×n matrix. p an equilibrated vectonal norm and x(A) the spectrial abscissa of A. Then, it is known 5] x(A)≤x(γ_p(A)) where γp is the matricial logarithmic derivative induced by p. We will make use of the above inequality to obtain regions in the plane which contain the zeros of complex polynomials.