• Permutation 2-groups I: structure and splitness 

      Elgueta Montó, Josep (2014-06-20)
      Article
      Accés obert
      By a 2-group we mean a groupoid equipped with a weakened group structure. It is called split when it is equivalent to the semidirect product of a discrete 2-group and a one-object 2-group. By a permutation 2-group we mean ...