Construction of Benford Random Variables: Generators and Seed Functions
  In this paper I describe two general methods of constructing a probability density function (pdf) of a Benford random variable, and show that the pdf of every Benford random variable may be constructed by these methods. These constructions are helpful in exploring the nature of Benford random variables, and may be used to investigate some issues of base dependency of Benford random variables. 
Frank A. Benford
math.GM