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On the indecomposability of unit groups

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  1. [1]

    J. Elstrodt,F. Grunewald, andJ. Mennicke,Groups Acting on Hyperbolic Space. Harmonic Analysis and Number Theory, Springer, 1998.

  2. [2]

    B. Fine,The Algebraic Structure of the Bianchi groups, Marcel Dekker, 1989.

  3. [3]

    P. de la Harpe andA. Valette,La Propriété (T) de Kazdan pour les groupes localement compacts, Astérisque175, 1989.

  4. [4]

    A.M. Hoare, A. Karras, andD. Solitar, Subgroups of infinite index in Fuchsian groups,Math. Z.125 (1972), 59–69.

  5. [5]

    E. Kleinert, Units of classical orders: a survey,L’Enseignement Mathématique 40 (1994), 205–248.

  6. [6]

    —, Two theorems on units of algebras,Abh. Math. Sem. Univ. Hamburg 70 (2000), 355–358.

  7. [7]

    G.A. Margulis,Discrete Subgroups of Semisimple Lie Groups, Springer, 1991.

  8. [8]

    J.P. Serre,Trees, Springer, 1980.

  9. [9]

    H. Zieschang, On decompositions of discontinuous subgroups of the plane,Math. Zeitschr. 151 (1976), 165–168.

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Author information

Correspondence to E. Kleinert or Á. Del RíO.

Additional information

Work on this paper started when the first named author spent some weeks in Murcia. He thanksÁngel del Río and the University of Murcia for inviting him. The second author is partially supported by the D.G.I. of Spain and the Fundación Séneca of Murcia.

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Kleinert, E., RíO, Á.D. On the indecomposability of unit groups. Abh.Math.Semin.Univ.Hambg. 71, 291–295 (2001).

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  • Unit Group
  • Free Product
  • Finite Index
  • Discrete Subgroup
  • Fuchsian Group