  A classification in universality classes of broad categories of
phenomenologies, belonging to different disciplines, may be very useful for a
crossfertilization among them and for the purpose of pattern recognition. We
present here a simple scheme for the classification of nonlinear growth
problems. The success of the scheme in predicting and characterizing the well
known Gompertz, West and logistic models suggests to us the study of a hitherto
unexplored class of nonlinear growth problems.
