An investigation was made of a standard model, for bistable reaction-diffusion-systems, which shared some characteristic properties with those of the van-der-Pol oscillator for distributed generators and with those of the FitzHugh-Nagumo system. In particular, a study was made of the effect of a long-range inhibitor. The main result was the discovery of the existence of 2 inhomogeneous stationary solutions. The smaller one was always a saddle which corresponded to a critical nucleus, while the larger one arose as a stable solution.

L.Schimansky-Geier, H.Hempel, R.Bartussek, C.Zülicke: Zeitschrift für Physik B, 1995, 96[3], 417-27