| Topology Atlas Document # taic-47 | Topology Atlas Invited Contributions vol. 8, no. 1 (2003) 8 pp. |
Joetsu University of Education, Japan
Mathematics Subject Classification: 54E20
This survey article was refereed anonymously.
Date published: February 20, 2003.
Copyright © 2003 by the author. Distributed by Topology Atlas with permission of the author.