1. Surfaces in three-manifolds and non-singular equations in groups

   • John R. Stallings

   OriginalPaper Pages: 1 - 17

2. Idempotents in group rings

   • Zbigniew S. Marciniak

   OriginalPaper Pages: 19 - 27

3. Homology spheres andS ¹-actions

   • Czes Kosniowski

   OriginalPaper Pages: 29 - 42

4. Construction of Auslander-Reiten quivers for a class of group rings

   • Ernst Dieterich

   OriginalPaper Pages: 43 - 60

5. Subspaces in hermitean spaces of countable dimension

   • Werner Bäni

   OriginalPaper Pages: 61 - 96

6. Endomorphisms of polycyclic groups

   • Bertram A. F. Wehrfritz

   BriefCommunication Pages: 97 - 99

7. On the geometry of positive maps in matrix algebras

   • Toshiyuki Takasaki
   • Jun Tomiyama

   OriginalPaper Pages: 101 - 108

8. Extremal quasiconformal mappings with free boundary components in domains of arbitrary connectivity

   • Richard Fehlmann

   OriginalPaper Pages: 109 - 126

9. The index of minimal immersions ofS ² intoS ²ⁿ

   • Norio Ejiri

   OriginalPaper Pages: 127 - 132

10. A short proof of a theorem of burns

    • Brigitte Servatius

    OriginalPaper Pages: 133 - 137

11. A note on baer groups of finite rank

    • Howard Smith

    BriefCommunication Pages: 139 - 140