On the parametric behavior of A-hypergeometric series
  We describe the parametric behavior of the series solutions of an A-hypergeometric system. More precisely, we construct explicit stratifications of the parameter space such that, on each stratum, the series solutions of the system are holomorphic. 
Christine Berkesch Zamaere, Jens Forsg{\aa}rd and Laura Felicia   Matusevich
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