"Phase portrait of the high-dimensional olfactory dynamics is
shown in two representative dimensions of the output of a
KO_{e} set and a KO_{i} set with
one KII set. Elevation is proportional to amplitude."

W. J. Freeman
Simulation of Chaotic EEG Patterns witha Dynamic Model of the
Olfactory System
Biological Cybernetics. vol.56, pp.139-150, p.146. 1987.