  By using an analogy with the case of very close zeros symmetric with respect
to the critical line of the Davenport and Heilbronn function, we study the
conformal mapping of L-functions in a neighborhood of a hypothetical double
zero and conclude that such a zero cannot exist.
  Keywords: Riemann Hypothesis, non trivial zeros, Ghisa's strips, Ghisa's
fundamental domains, Ghisa's intertwined curves
  2010 Mathematics Subject Classification: 30C35; 11M26
