Havas, GeorgeNewman, MichaelO'Brien, E A2015-12-132015-12-130092-7872http://hdl.handle.net/1885/79432We describe a new technique for finding efficient presentations for finite groups. We use it to answer three previously unresolved questions about the efficiency of group and semigroup presentations.Keywords: Efficient presentations; Finite groups; Finite semigroups200410.1081/AGB-1200279202015-12-11