1. Department of Mathematics Victoria University of Wellington Wellington, New Zealand ddiamondstone@gmail.com
2. Department of Mathematics Victoria University of Wellington Wellington, New Zealand greenberg@msor.vuw.ac.nz http://homepages.mcs.vuw.ac.nz/~greenberg/
3. Department of Mathematics Victoria University of Wellington Wellington, New Zealand dan@msor.vuw.ac.nz http://homepages.mcs.vuw.ac.nz/~dan/