The EMIS web site has a lot of links of that type - there's a link to it from my "links" page )off of my home page) Neil Neil J. A. Sloane AT&T Shannon Labs, Room C233, 180 Park Avenue, Florham Park, NJ 07932-0971 Email: njas at research.att.com Office: 973 360 8415; fax: 973 360 8178 Home page: http://www.research.att.com/~njas/