Marc Giusti Grégoire Lecerf Bruno Salvy Jean-Claude Yakoubsohn On Location and Approximation of Clusters of Zeros of Analytic Functions. 257-311 2005 5 Foundations of Computational Mathematics 3 http://dx.doi.org/10.1007/s10208-004-0144-z db/journals/focm/focm5.html#GiustiLSY05