TY  - DATA
AU  - Guba, Victor
AU  - Sapir, Mark,
TI  - Diagram groups 
T2  - Memoirs of the American Mathematical Society, 
SN  - 9781470402099 (online)
PY  - 1997///
CY  - Providence, R.I.
PB  - American Mathematical Society
UR  - http://www.ams.org/memo/0620
ER  -