Michèle ARTIGUE
IREM, Case 7018
Université de Paris VII
2, place Jussieu
F-75251 Paris - Cedex 05
F r a n c e artigue@ufrp7.math.jussieu.fr
Nataliya BANTSUR
Institute of Mathematics of the
National Academy of Sciences of Ukraine
Tereschenkivska Street, 3
01601 Kyiv
U k r a i n e natasha@imath.kiev.ua
Hyman BASS
4204C School of Education
610 E. University
University of Michigan
Ann Arbor, MI 48109-1259
U. S. A. hybass@umich.edu