In yesterday's (Tue, Jul 29) Wall Street Journal (!), a front page article talked about David P. Robbins's search for a generalization of Heron's & Brahmagupta's formulae for the area of polygons inscribed in circles, when given only their edge lengths. The article indicated that Dr. Robbins was using only pencil & paper, which I found a bit odd, considering that there are a number of symbolic algebra systems that I would imagine would be quite useful for this problem. I searched the web, but the only publications I could find by Robbins on this subject were: Robbins D P Areas of polygons inscribed in a circle, Discrete Comput. Geom., 12 (1994), 223--236 David P. Robbins. Areas of polygons inscribed in a circle. Amer. Math. Monthly, 102(6):523-530, 1995 Apparently, he has found generalizations to pentagons and hexagons, but 7-sided figures currently has him stumped. The following paper talks about these papers: www.geocities.com/teufel_pi/papers/cyclic.ps.gz Dr. Robbins works here: http://www.idaccr.org, and this is his email: david.robbins@idaccr.org I could not find a personal web page for Dr. Robbins.