Asymptotic fitness distribution in the Bak-Sneppen model of biological   evolution with four species
  We suggest a new method to compute the asymptotic fitness distribution in the Bak-Sneppen model of biological evolution. As applications we derive the full asymptotic distribution in the four-species model, and give an explicit linear recurrence relation for a set of coefficients determining the asymptotic distribution in the five-species model. 
Eckhard Schlemm
q-bio.PE math.PR