Alexander N.Dranishnikov Department of Mathematics, University of Florida, Gainesville, Fl., U.S.A.
Steven C.Ferry Department of Mathematics, Rutgers University, Piscataway, New Jersey, U.S.A.; and Department of Mathematics, Binghamton University, Vestal, New York, U.S.A.
ShmuelWeinberger Department of Mathematics, University of Chicago, Illinois, U.S.A.