  Using the criteria of simplicity, positivity, smoothness and process-
independence of construction, we find a non-polynomial model for the quark
distribution amplitude of the nucleon that is in agreement with QCD sum-rule
constraints. This simpler ("haplousterotic") model solves some of the problems
connected with the longitudinal momentum dependence of the wave function,
whereas the k_T-dependence of the wave function, which is also important, is
still left undetermined. The expansion pro- perties of the model into a
polynomial series are examined.
