00343nam a2200121Ia 4500082001600000100001900016245005000035260004800085300002200133490005600155500000500211700000500216  a512bJ66.TT  aJohnson, D. L.  aTopics in the theory of group presentationsb  aCambridgebCambridge University Pressc1980  aviii, 311p. Index  aLondon Mathematical Society lecture note series, 42  a  a