Page maintained by
and last modified on Oct. 18, 2014.
This page's URL is: www.math.ubc.ca/~gerg/index.shtml?abstract=DEF
This page, and all files on this server linked from it, are ęGreg Martin and are not to be copied, used, or revised without explicit written permission from the copyright owner. (Some manuscripts have had their copyright assigned to the journals in which they are published).