Edward N. Lorenz, "Deterministic Nonperiodic
Flow", Journal of TheAtmospheric Sciences,Vol. 20, March 1963, pp. 130-141.
It is at multiple locations in the web. One source is:
http://www.astro.puc.cl/~rparra/tools/PAPERS/lorenz1962.pdf
At Cornell I took John Guckenheimer's and Steve Strogatz's courses, inaddition to
the more EE-focused nonlinear systems course taught byHsiao-Dong Chiang. Really beautiful
stuff.
carlos.