caa a22 4500 386372152 CHVBK 20180307112001.0 cr unu---uuuuu 161130e198909 xx s 000 0 eng 10.1017/S0017089500007849 doi S0017089500007849 pii (NATIONALLICENCE)cambridge-10.1017/S0017089500007849 Hannebauer Torsten Humboldt-Universität zu Berlin, Sektion Mathematik, Unter den Linden 6, Berlin, GDR—1086 Relation modules of amalgamated free products and HNN extensions [Elektronische Daten] [Torsten Hannebauer] Let G be a group and a free presentation of G, i.e. a short exact sequence of groups with F free. Conjugation in F induces on = R/R', the abelianized normal subgroup R, the structure of a right G-module (if r R, x F then (r)(xπ) = x-1rxR'). The G-module is called the relation module determined by the presentation (1). For a detailed discussion of this subject we refer to Gruenberg [3]. Copyright © Glasgow Mathematical Journal Trust 1989 Glasgow Mathematical Journal Cambridge University Press 31/3(1989-09), 263-270 0017-0895 31:3<263 1989 31 GMJ https://doi.org/10.1017/S0017089500007849 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1017/S0017089500007849 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Hannebauer Torsten Humboldt-Universität zu Berlin, Sektion Mathematik, Unter den Linden 6, Berlin, GDR—1086 NATIONALLICENCE 773 0- Glasgow Mathematical Journal Cambridge University Press 31/3(1989-09), 263-270 0017-0895 31:3<263 1989 31 GMJ CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-cambridge