References
  
  [Bre89]    Bressoud,   D.   M.,   Factorization   and   Primality   Testing,
  Springer-Verlag (1989).
  
  [Bre96] Brent, R. P., Factorization of the Tenth and Eleventh Fermat Numbers
  (1996),                                                                    (
  ftp://ftp.comlab.ox.ac.uk/pub/Documents/techpapers/Richard.Brent/rpb161tr.dvi.gz
  ).
  
  [Bre04]      Brent,      R.      P.,     Factor     Tables     (2004),     (
  http://web.comlab.ox.ac.uk/oucl/work/richard.brent/factors.html ).
  
  [Coh93]  Cohen,  H.,  A  Course  in  Computational  Algebraic Number Theory,
  Springer-Verlag (1993).
  
  [LN17]  Lübeck,  F.  and  Neunhöffer,  M., GAPDoc (Version 1.6), RWTH Aachen
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