closed forms are exact--Poincare ?

From: Van Jacques (calccurve-test23_at_yahoo.com)
Date: 09/17/04


Date: 17 Sep 2004 04:58:57 -0700

Is the theorem that closed forms are exact called Poincare's thm.?
I forget. Or is ddf = 0 (or dd = 0) called Poincare's thm.

I did a search and got a bunch of stuff about Poincare's recurrence thm.