@book{UBHD-3501364, author={Rimlinger, Frank}, title={Pregroups and Bass-Serre theory}, publisher={American Mathematical Society}, address={Providence, RI}, year={1987}, pages={VIII, 73 S.}, language={eng}, isbn={0-8218-2421-X and 978-0-8218-2421-4}, number={ARRAY(0x557650dc1ac8)}, series={Memoirs of the American Mathematical Society}, library={UB [Signatur: 88 W 24] ; MA [Signatur: Rimli]}, }